Here is an interesting peek at the art and culture surrounding music sampling from the late 1980s. It looks like it was a long piece or in-depth look that would have run on Mtv new (I think that is Kurt Loder narrating). It has some technical information on how its done, a discussion of its positive and its negative effects.
All that is great, but what I really enjoy are the interviews. If you forward to about the 1:50 mark, you will see a young Fresh Prince (Will Smith) call James Brown “old” and “over”. But thanks to rap and sampling, James Brown was “new” again and worthy of our attention. I think you will agree, this is just about the classiest think you can say about a music legend.