http://www.wow-professions.com/
Not my work but I ran across this site and I've used it many times, so I thought I would share it.
Lootables: World of Warcraft Item Database Search (Page 1/1349) is alright as well, and its been posted here before. It's not purely focused on professions like http://www.wow-professions.com/ so I don't feel it's as in depth.