anyone know of a free mp3 to wav converter for linux?

It looks easy enough to just do it from the command line..

http://www.patoche.org/LTT/sound/00000122.html

Any GUI version or graphical frontend?

Are there any graphical mp3 to wav converters available for linux?

you can use xmms for converting mp3 to wav.
use the disk writer plugin.
in the preferences, set the output plugin to disk writer. play the file you want to convert. the file will not be played (i.e. is no music), but you will get a wav file of the mp3.

Brilliant! Thanks.