I'm late, I know!

For number 2 in the general search area I have never read a fic better then rei_c's 5 Districts, 5 Drugs verse.
Here's the tag (http://rei-c.livejournal.com/tag/5d5d) but it's a bit confusing. What I would suggest is to go to her SPN master fic list (http://rei-c.livejournal.com/685721.html) and scroll down to the label 'The Five Districts, Five Drugs series'. It lists the order they should be read in.

Each story is a new district and a new drug though each district starts the same and ends the same. There are 5 main stories within the verse(and from them spin other stories which is where it gets confusing) and an Epilogue

The basic storyline for each story is that Dean needs to find Sam so that they can kill the demon together. Sam has run away from Stanford and is addicted to drugs. The story carries on from there, taking whatever twist for the specific senario.
Just a warning; there's wincest, graphic sex, S/M, whoring, dub-con. It's pretty heavy.

Sorry to babble on so much, I just really adore this verse :)