Avidemux

So here goes another software tip: Avidemux. It is a video encoder with some really great options and really easy to use. I particularly use it to encode videos for my palmtop, and it works great. It has some automatic encoders built-in, like an iPod encoder, which may come in handy if you own one.
So, to install it, easy as pie:

$ sudo apt-get install avidemux

Then to use it just right click the audio file and then "OpenWith...advidemux". The interface is very intuitive.

Cheers.