About ID3 tags. MP3 files can contain information about the song within the file itself, such as artist and track number, so you don't have to mess with putting all that information in the filename. This page discusses the basics for the purposes of AppleScripting with iTunes. I'm mostly interested because I have MP3 players that don't support ordering by the track number ID3 field, and I'd like to find or write a utility to either rename files ripped with iTunes based on track number, or generate M3U playlists in album order.

Of course, seconds into this bit of research I find software that does exactly what I want: iTunes Publisher (for Mac) converts iTunes library lists into M3U files. I also understand from minimal research that iTunes saves its library information as an XML file (read-only, it won't recognize changes in the XML file).