If you aren't looking for anything in particular you should check out the crossover-pages on Fanfiction.net

Teen Wolf: http://www.fanfiction.net/Supernatural-and-Teen-Wolf-Crossovers/2237/8413/3/0/0/4/0/0/0/0/0/0/1/0/

I just posted a TW/SPN crossover for the Supernatural Crossover Big Bang called Of Wolf and Man (http://twisted-slinky.livejournal.com/74886.html). Summary: After receiving a call from an old family friend, the Winchesters find themselves in Beacon Hills, CA, finishing a case they started in their teens, back when the creature of the week was hunting a young deputy named Stilinski and his pregnant wife. Now, the monster is back, and the hunters are needed, but there's more than one threat in this small town, and the guys are starting to think Deaton called them in for an entirely different reason, one involving a few secrets John Winchester kept past the grave. Gen. SPN season 8; TW post season 2.

These are all the walking dead/supernatural crossovers:

Clean by Jenasys Loveless Lovecraft on ff.net (Pairing: Destiel and Caryl)
Link:https://m.fanfiction.net/s/8742826/1/Clean

The Walking Supernatural: A SPNWD Crossover by daksgirl on ff.net (Pairing: Destiel)
Link:https://m.fanfiction.net/s/7557692/1/The_Walking_Supernatural_A_SPNWD_Crossover


Haven by miss_grey on AO3 (Pairing: Destiel, Glenn/Maggie and Sam/Sasha)
Link:http://archiveofourown.org/works/2953769/chapters/6529115