I love me some dubstep:
These should get you started:
http://youtu.be/1QqY-8mohxo (my personal fav)
http://youtu.be/XiojdDs8wwk
You've already found skillrex (pretty much anything of his is awesome).
bangarang
my name is skillrex
http://youtu.be/mFenwj2kLJk
There is so much to like. Please keep sharing your favs though, as I'm always looking for better/good/new...
It's the best workout music by FAAAAAAAAAAAAAAARRRRRRR