He looks like a sweetheart! I've got two dogs already so I can't take him, but I'll keep my ears open. I found both my dogs through craigslist, I suggest placing an an for him on there, along with other adoption sites.
Good on you for fostering him and not just taking him to a local shelter. He looks like he may some pit in him, so if you don't have any luck finding a loving home, check out L.A.'s Pit Bull rescue for abandoned pits:
http://www.vrcpitbull.com