A listener to the Geek News Central Podcast named Sam sent me this info, I think you will all get some value out of it.
How to backup and protect songs you have purchased from Apple iTunes so that when your computer dies you will not loose your investment.
1. Run Jhymn http://hymn-project.org/jhymndoc/ and remove all drm from all m4p and m4b files! I am not sharing these files so I see no ethical issues with this regardless of what that travesty known as the DMCA says. Make sure you follow the “Big secret” instructions that jhymn provides. This will strip everything so that future itunes updates cannot re-enable the drm on the files.
2. Jhymn automatically backs up the original locked files to a separate directory. I search the hard drive for all m4p, m4b and m4a files. I back these up to an external hard drive AND data cd or dvd. The unlocked files can always just be dragged back to the hard drive and dropped on the open itunes window for re-importing in the event of a catastrophe. This way if your net connection goes away or itunes music store goes away, I still have the music that I have PURCHASED (not rented).
3. You can also create a playlist of purchased music and burn it to music cds.
Officially apple does not support re-downloading music files. They expect you to do your own backups. However I have read in the past that if you contact Apple Customer support and have all your info they may make it possible for you to re-download your music. No guarantees on this one though.