Is it possible to recover lost info on an ipod classic?

Hi all, I have a classic 20GB ipod which had 11Gigs of my favorite heavy metal stored on it. My p.c. died and upon re-installing itunes, would not recognise my ipod at all. I eventually took the plunge and hit the delete all button (reformat I think) which has brought up music I have never seen or owned and I now have an 11GB file in orange (other)at the bottom of my library page as well as the blue bit which is the music on it. Can anybody help me out??even if I have to start from scratch. Cheers