For me it's:
Anal - Only advertising one, but AssTraffic from Perfectgonzo does pretty well for me
Mature - Oldie but goldie, MilfHunter from Nastydollars, plus OlderLadies from Oxcash (the site doesn't seem to update any more, but I got members rebilling from 2002...)
Teen - All the Diesel sites, Young Porn especially
Ebony - Not really my niche, but interracial ads for VideosZ pull good, surprisingly white guys on black girls do better than black guys on white girls
