If you want to get a sense of all the samples that go into a Girl Talk song, I recommend the following which provides real time info of each sample as the song plays:

http://readyrickshaw.com/toob/node/63 -and- http://alldaysamples.com/

I think this is presented much better on MashupBreakdown. They also have more artists.

http://mashupbreakdown.com/