Try searching the computer for one of the song titles using finder.
where were the songs files before you lost them? Were they in your iTunes folder, or elsewhere? Sometimes they seem to find a home in the Limewire folder in applications which is the worst place they could be, as they would be deleted if you deleted Limewire.
go to Limewire > preferences>saving > what is the location of your save folder? is this the same as it was before your "virtual relaunch"?
If you can't find a file as I mentioned this link contains information on trying to restore lost files and possibly it might help.
http://www.gnutellaforums.com/showth...threadid=49851