If you haven't already, check out ParadigmDVD's youtube channel. Since they stream and post comps, there's so much music for you, I've gotten tons from there. But sometimes you won't be able to shazam/soundhound the songs because they slow or quicken the tempo quite significantly, but sometimes I google the lyrics and that works. Check it out!
Oh, and ballroomdancers(dot)com has lists of songs, all organized by dance style.