ptemp

sox

Sound Converter is a graphical tool that uses gstreamer as its back end.
http://soundconverter.berlios.de/

If you prefer command line tools, or want more control over your conversion, give ffmpeg a try. ffmpeg is designed for video conversion, but it converts audio quite nicely as well. The basic command for ffmpeg is “ffmpeg -i example.ogg to example.mp3”. It only converts one file at a time, so wildcards are out of the question. In order to convert large quantities of .ogg files you must use the following small script:

for x in *.ogg; do ffmpeg -i “$x” “`basename “$x” .ogg`.mp3″; done

http://www.igso.net/nkb/Converting_ogg_to_mp3_in_Linux

soundkonverter

Audacity and the LAME codec succesfully for this purpose of converting single files.
But if you have the CD’s then why not use the Soundjuicer application?

http://packages.ubuntu.com/lucid/sound/soundconverter
http://packages.ubuntu.com/lucid/sound/soundconvert
http://packages.ubuntu.com/lucid/sound/nautilus-script-audio-convert