monline

Ubuntu (and probably most other distributions) have all the tools that you'll need: Mplayer and Lame. Use the former to capture the stream into a RM (=Real Media) file:
Now convert the Real Media file to a WAV:
And finally convert the WAV into an MP3:

I've already found out how to use VLC to play Quicktime videos. Now I've faced some issues with WMV files. VLC did not play the WMV properly (it showed some "noise" instead of the real content), neither did any other player (like Kaffeine, Xine, Mplayer). For Xine I had to set the video output from "auto" to "xshm". For Mplayer I had to choose the "X11" video setting (this can be set globally in /etc/mplayer/mplayer.conf).