James Lipton interviewed the actors that do the voices for The Simpsons, and a kind soul uploaded the video to YouTube.  It’s divided into three parts. Enjoy!

http://www.youtube.com/watch?v=No2_-X3_hmE

http://www.youtube.com/watch?v=SFSvniz_wNc

http://www.youtube.com/watch?v=x1q85qa6Pbc