Thanks guys. It's my own fault & too late now.
The original drive started acting weird yesterday... I'd open the song & it couldn't find certain files. Finally it wouldn't mix down at all. Then it crashed. So I transferred everthing to my second drive. Made room on my first drive, re-installed the system and transferred it back. Everything was working fine, so I erased the one off my second drive.
When I went back to the first drive again, I realized all the files that the song were pointing at were located on the second drive. So the song's intact, but there's no .aiff files left.

I already went throught the whole Norton recovery thing... all day... blah.
There's portions of the song files left but about 90% of em are gone cause both drives were filled to capacity & I'd already started erasing other stuff.
Even if I did find them all, I'd have to spend 2 weeks figuring out which ones were which and reconstruct the song from scratch anyways so to hell with it.

...and my last thought before hitting the 'empty trash' button was "I've got this backed up on disc... don't I?... yeah of course I do!"