I am not up to date on recovery software, but the most important thing is that you do not perform any write operations to that hard drive.
Windoze does writing anyway and there isn't much you can do about that, but don't make it any worse.
Personally I have used a program called FinalRecovery, version 1.2, to unerase files from flash media (e.g. digital camera media) with great success. Most unerase programs do not work on removable flash media, accessed via USB-attached media readers. But I can't speak for FR on hard drives, especially with different types of partitions.