http://wrenseroticlibrary.tumblr.com/post/55359707075/act-your-age-part-one

An already bizarre case goes full-on freaky when Sam’s 27-year-old mind gets stuck in a 12-year-old body. Of course he and Dean are determined to get to the bottom of this… but they may get sidetracked a bit.

Parts 2 and 3 have library sex:)

This is a J2 one, but I think you might enjoy it. :)

In The Stacks (http://ladyfoxxx.dreamwidth.org/2898.html) - by ladyfoxxx

For #2:

Brand New Start (http://gestaltrose.livejournal.com/34373.html) and Find His Way Back (http://gestaltrose.livejournal.com/45791.html) by gestaltrose: "Jared Padalecki is one messed up kid, after his parent die he his tossed from Foster home to Foster home slowly losing everyone he loves. He's given one last chance with the Ackles. Can he come to peace with his past? Will he admit that he's attracted to Jensen? AU story of a hurt boy who's trying to find some peace and maybe, if he's lucky, love." (heed the warnings on this one)

All the Way Home (http://archiveofourown.org/works/215789)by peggy_lane: "When his life went to hell, Jensen left Dallas and moved to the small family ranch to start over. It's a lonely, solitary existence until he hires Jared to help out around the place. Jared's a temptation that's hard to resist and Jensen finds himself beginning to live again. But ranching isn't his calling, and Jared's running from some demons of his own; he's not the type to stick around. They're temporary, and Jensen thinks he's fine with that, but letting go has never been so hard to do."

The Shortest Distance (http://archiveofourown.org/works/3261524/chapters/7112558) by compo67: "The year is 1935 and the Great Plains are hurting. Beaten down, dirt and dust-laden, the people of these Plains live in a constant haze. Jared is twenty years old and struggling to keep his adoptive family alive and cared for. When his husband Cole died, much of the faith in this land died with him, though they have stayed because this is their land. They stay because they belong here. Cole’s cousin arrives in from Montana two years too late, seeking to uproot his kin and change their lives. With nature against man and man against nature, no one remains the same." (LOVED this one)

Finding My Way Home Started with Finding You (http://ladyrhyanne.livejournal.com/13130.html) by ladyrhyanne: "Scott McCoy is searching for who he is, literally. Seven months ago he woke up from a coma with no memory as to who he is or how he ended up in the hospital in the first place. Not entirely content at the ranch he has taken refuge at but not exactly ready to face an unknown past he`s convinced himself to stay until he has more money saved up. That is until the sleepwalking and the dreams start then he knows he has to start searching for the life he`s forgotten."

Happy Plastic People (http://www.sinful-desire.org/archive/viewstory.php?sid=4447) by anyothergirl415: "In the wake of his family’s hatred, Jared is left to deal with the pieces of himself. Being friends with a perfect Christian boy like Jensen is downright terrifying but Jared can’t seem to stay away."

That Padalecki Kid (http://maddys-slash.livejournal.com/85770.html) by apostrophee: "Jared’s got a secret." (this one's kinda dark)

and in case you're also interested in ranch-setting Wincest fics:

The Consequences of Falling (http://archiveofourown.org/works/1142844/chapters/2312717) by colette_capricious: "Sometimes when you evaluate the same old actions through new eyes, certain truths become self-evident. Or we see what we expect to see."

#3: Shy Jensen
Driven (http://archiveofourown.org/works/3270635): Jared Padalecki is the star of television's hottest drama, "Drive." Low profile and genuine good guy, he agrees to meet up at a local dive joint with a guest star, Christian Kane, who introduces him to his roommate, Jensen. Jensen Ackles is a hard-headed, driven musician with an entire stack of emotional baggage from dating an actor when he arrived in L.A. He and Jared seem to hit it off right away, but can they make it last?

I Could Be Wrong About You (http://archiveofourown.org/works/2956328): Jensen was going to change his whole life around when he reached college. He was going to have lots of friends, take some interesting classes, and stop being so self conscious. If only his roommate wasn't a jerk.

The Treat Fairy (http://bbsock.livejournal.com/1642.html#cutid1): Jared hasn't been able to catch the person who is leaving him the pastries - someone is baking Jared the most delicious sweets; one day there was even homemade candy (every now and again there are homemade doggie treats for his babies too). When it first started happening, all his friends told Jared it was dangerous to eat random food that an unknown person was cooking for him, they were worried that he could be poisoned. Jared thinks everyone is just paranoid, no one who bakes likes this is dangerous. Jensen has a crush, and when he gets nervous he bakes. He noticed that his crush - his hot tall neighbor - likes sweets, so he gives all the results of his nervousness to Jared. The fact that Jared seems to like his baking just makes Jensen even more nervous.

Jensen Ackles Doesn't Exist (http://xen-fic.livejournal.com/3073.html): In hindsight he realizes that, had he just stayed put, had he not worried about the shoelace sticking out from under the desk where he was hiding, they probably wouldn’t have seen him. But they did.

Grapes of Wrath and Other Forbidden Fruit (http://astri13.livejournal.com/101306.html): Jared Padalecki only knows one goal in life: revenge on his twin brother Jeffrey who stole their family company. A chance encounter with Jeff's shy fiance Jensen might give him the perfect opportunity to get it.

Baby Steps (http://archiveofourown.org/works/1772821): Jared's a cop in a small Texas town. He comes from a well known and wealthy family but wants to make it on his own when he can. He knows if he has a weakness it's his soft heart...a soft heart that takes a hit when he finally meets his new neighbors. Jensen came from money but when he refused his family's demands to give up his child, he was kicked out and disowned. Now on his own with a six-month old baby he struggles to survive in a new town with very little money, no help and now no job.

Jensen doesn't stay shy, but the series is fucking glorious, and there are three long-ass sequels if you like the first story: Smoke & Lightning (http://arealwildchild.livejournal.com/9553.html). Jared's a leather-clad punk from the wrong side of town, and the only things that matter to him are his motorcycle, his stepfather, his extended biker family and his tattoos. Jensen's a rich kid who's going places, if he can only survive the bullying he gets at school for being gay, and the bullying he gets from his father for not being the person his father wants him to be. When their two worlds collide, will Jared be too much for Jensen to handle, or will he be the salvation Jensen's been looking for all his life?

#3 - Shy Jared/Sam

From the Outside, Looking In (http://annie-46fic.livejournal.com/114133.html): Jensen Ackles is young and privileged; his parents are rich and powerful and he has everything in life that he has ever wanted. When his mother decides to help an immigrant Polish family with their own problems will his opinions change? Or will his prejudice blind him?

Bring Me To Life (http://archiveofourown.org/works/379484): Jared’s a shy young man, whose life has never been easy. His father hates him, his mother drinks her sorrows away and his husband Paul condescendingly treats him like he is nothing more than a beautiful toy. When his husband has to go away on a business trip to Europe for two months, he sends Jared away to a ranch in the middle of nowhere to keep him under control. There, Jared meets people who show him what love, friendship and loyalty mean for the first time in his life. Can he escape his life and finally find some love and happiness for himself?

Then Again, I Just Might (http://archiveofourown.org/works/306473): It's not totally weird to be in love with a person’s voice is it? If it is, Jared's pretty much okay with being weird. Jensen is a DJ and Jared ... well, he suddenly loves his radio.

The Convergence of the Twain (http://fairygrrl45.livejournal.com/13408.html): Jensen doesn't really understand why this kid's so special, and Jared can't really explain what it is about Jensen that makes him want to be happy, but neither of them can walk away from this. Because Jared needs someone to see him, and Jensen needs someone to hear him, and who would've thought they'd find their whole in another half that's just as broken. Jensen is an anchor in Jared's storm, Jared is a light in Jensen's darkness, and neither of them wants to give up on what they've never thought they could have. It's a meeting that shakes the foundation to two worlds indelibly, this convergence of a twain.

Lost Time AU (http://archiveofourown.org/series/37316): Sam Burton has an average life, a foul-mouthed tattoo-artist sister named Ophelia (call me "Ope"), and a dream of putting his terrible, abusive past behind him. All of that changes when injured hunter Dean Winchester comes to stay.

Edited 2015-04-06 05:46 pm (UTC)

For #1:

I couldn't find any Sam/Dean sex-in-a-library fics, but this one has J2 kissing in a library? Life is Just One Cup of Coffee After Another (http://users.livejournal.com/__tiana__/134877.html) by tiana: "AU. Jared works at the campus Starbucks, and every day at 4:30, a guy comes in and orders the same drink."

And J2 recs has a whole list of sex-in-a-library fics here (http://j2-recs.livejournal.com/tag/sex%3A%20in%20a%20library).

For #3, you could poke around this list of J2 shy recs (http://j2-recs.livejournal.com/tag/shy). I especially loved I Pine for You, I Even Balsam (http://blackrabbit42.livejournal.com/43541.html) by blackrabbit42: "Jensen is unable to talk for whatever reason. He has a HUGE crush on his neighbor, so Jensen proceeds to leaved embroidered pillows on Jared’s doorstep (think dirty Charlotte’s Web). Jared has no idea who his secret admirer is."

#2 (Farm/Ranch setting):
* I Leave My Heart in the Dust Where You Walk (http://akintay.livejournal.com/187483.html): Jensen's life is pretty simple: he runs the ranch his parents left him, spends what little time off he has with his best friends, and occasionally drives for miles to hook up with men he will never have to see again. He tells himself he isn't really gay and that he's happy with the life he leads. But then Jared – tall, beautiful and vibrant – arrives on the ranch looking for work, and Jensen begins to question who he is and what he really wants. Featuring: puppies, horses, skinny dipping, mud fights, sex in a hayloft, and meddling best friends.

* The Long Way Home (http://archiveofourown.org/works/264347): Eighteen years old and fresh out of foster care, Jared Padalecki goes looking for answers about who he is and where he came from when he reads his father's name on his birth certificate. But he wasn't expecting to find what was waiting for him... six brothers and a guy he just can't resist.

* Bring Me to Life (recommended for #3 in a different post) in large part takes place on a ranch.