I once did a similar recovery for a friend of mine. He reinstalled windows including a format and forgot to backup his wallet. Big panic from his side, he installed a lot of shitty tools trying to recover the file.

DONT DO THIS!

Shutdown your pc - no, dont use the "shutdown" in windows, just cut power off.

Get a linux recovery or live-cd and boot your pc from it. make sure it does not write anything to your disk!

Now you can start recovering.

I recommend mondo or scrounge-ntfs for ntfs. They are built-in into most live-cd's.

If everything fails there is still hope:
there is a specific structure inside the wallet.dat-file, for example it contains lots of "blockindex"-strings, your public addresses (you can still get them, for example from your pool, do you?) and some more.

i wrote a little tool that searches your whole harddisk for this structure and recovers all private keys it finds - even if there is no reference to the file in the file system, even if the file is partially overwritten - and generates a new wallet.dat file from it.

Write me if you need more help!