Ok, I won't go into the ugly details but suffice it to say I recently lost a file I really, really wanted back. I realized it following the re-install of WinXP on the same drive. Um..big oops!
I tried two products unsuccessfully and felt increasingly ill that my missing file was not being found. On what I had already determined was going to be my third and final attempt, I used the product Active @ UNDELETE. It was great! It found far more files than its competitors and, most importantly, it found the file I really, really wanted back. And, thus, I highly recommend it. ;-)
The only thing I didn't like about it was that the demo version couldn't be converted to a full-working version with the purchase of the license key. I had to re-install the paid version. The reason that's a big deal is that it means you have to do the search of the hard drive all over again to allow the paid version to able to do the recovery process. The demo version is limited to files that are 64 KB or smaller. I was a bit worried that my essential file was going to be written over during the install of the paid version, but the computer gods were kind to me that day and gave me back my file. And re-doing the search process is slow.
May you never need this advice!