Ahaha... I've had fun with those before... I've written some lovely reggae and mixed showtunes with hip-hop. (Just ask SoulRebel51)
Most hip hop and rap beats are made from old funk samples.... here's a good site for beats, there's a good 600+ of them.... http://www.phatdrumloops.com/old_site/
and one more, this is a specific thread on the site... if you go the "the grid" message board on www.dogsonacid.com you'll be in electronic producer heaven....it's a drum and bass site, but for loops, sounds, program information; those people really know their shit http://www.dogsonacid.com/showthread.php?threadid=32194
I've got a number of hip hop drum loops and plenty of others on my site. http://www.loopartists.com/free-loops.php?c=Drums&g=HipHop&pg=1