I am not sure where a .wav of it is, but if you use
http://download.cnet.com/Free-YouTub...#editorsreview you should be able to download a youtube video that has what you want.
Just be careful of spyware and stuff that comes attached sometimes in these things. I prefer download.cnet.com because they usually get rid of that stuff, so it should be good. You may try a different youtube downloader though