There is a program here to download Youtube videos:
http://comunidad.uem.es/epuertas/post/2006/06/01/como-descargar-videos-youtube-google-video-y-grinvi
Latest version: VDownloader 0.6
I have explained here how to use it:
http://29984.rapidforum.com/topic=102373698317
Or you can save it as mp3 using Audio Recorder for Free http://29984.rapidforum.com/topic=102571739004