GetDataBack is the best in its price range. If the trial version finds the files it won't recover them until you purchase the full version, but at least you'll know they are recoverable.
You could also try the freeware
PC File Inspector. I've used this to recover data from formatted and corrupt drives.
Try not to use the computer until you're ready to run a recovery program or you might overwrite the file locations. Also, you'll get better results if you can write the recovered files to a separate drive. This is to avoid the 'lost' files being potentially overwritten by the recovery process.