Here's what someone on another site recommended to fix a similar problem.
http://forums.ilounge.com/itunes-mac-pc/41538-please-help-itunes-lost-all-my-playlists.html
Just restore the .itl file from your latest backup. Shut down iTunes, replace the file, restart iTunes, done.
...Essin did not give vague directions. He gave directions, that if a person does not have a "recent" backup of their .itl file, would make no sense.
Here is a lessen for everyone. the .itl file IS iTunes, without it you have an empty library. This file is so important that it should be part of a weekly backup program at least, and always backed up immediately after any major playlist creation or library changes.
If this file would have been backed up by the original poster that would have to have been done is
Quote:
Just restore the .itl file from your latest backup. Shut down iTunes, replace the file, restart iTunes, done.
Basically replace the .itl file in \My Documents\My Music\iTunes folder with the .itl you so smartly have been keeping as part of a back up strategy.
The temp file strategy sometimes works, but is not a reliably backup to a dedicated backup of the .itl file on a regular basis.
Cheers.
Failing having a back up of the .itl or the temp file solution failing, occasionally some playlists and some metadata can be retrieved from a fully synced iTunes library from an iPod, if you have an iPod that can carry your entire library. With the correct program.
The temp files aren't always available they are supposed to be deleted after they are written to the .itl. They are never reliably available on the mac platform, they seem to hang around longer on the windows platform, but depending on what you do after such a disaster a more recent temp file could just be a temp file full of the new "bad" library.
Good luck.