i don't listen to anything but rap, though i don't mind whether its from the USA or UK, i love both!
usa:
eminem, all of G-Unit, Nas, 2Pac, Jay-Z, The Game, Dre etc etc!
uk:
kano, dizzee rascal, braintax (n all of lowlife records: jehst, klash, taskforce etc..),
Street Poets