Try partition table doctor and see what the free demo can find :
http://www.ptdd.com/ (rebuild partition table).
You could also try
Active @ Partition recovery or
Active @ Undelete.
The free demos will tell you if they find something but you'll have to pay to recover your data. If none of those commercial tools can find anything then there's a big problem...
Edit : I'll move you to the hard drive support section, they may have other things to try.