hehe, people are real quiet about their samples for the most part, to me 70's is the best era for samples...funk,soul,soundtracks,progressive,rock whatever(i'm not sure what sound your going for). Since your starting out i assume your going to be simply taking a few bars and looping, not really chopping/mixing up so you'll want to find stuff you can easily mess with. Actually the best way to go about it is search in google for the original samples of artists you like...find those artists,and get some of their other work, find bands catergorised as similar etc....thats my advice for you to start out.