Originally Posted by
mixture
Erm, iTunes already stores as MP3 ?
Not necessarily. It will work with MP3s if you have them, but the format for tunes downloaded from the iTunes Store is
M4A. There are all kinds of M4A to MP3 conversion options, but some may not work with the "rights management" on iTunes downloads.
(That site has more details about the format, but don't fall for the "MP3s sound inferior" nonsense. The sound quality depends on how you encode them, and that applies to all lossy compression formats, including M4A. Where possible I use VBR 0 encoding on MP3s, I can afford the disk space.)