Help me to recover backup file after format / install XP

I have a huge problem!  I was re-installing windows on my wife’s computer, and so backed up all her files using the WD backup utility to a 500Gb “my passport” drive.  Feeling satisfied that all was safe, I then I reinstalled Windows, and chose to reformat the drive - only I reformatted the WD backup drive (using quick format) instead of the main C drive! And what is worse, windows copied the install files over onto the newly formatted drive, meaning that there will be data loss.

I now have no backup(s), and the standard NTFS recovery tools I have tried don’t seem to recognise the format of the WD backup files, so they can’t see them.

The newest backup was one of a number of backups on the drive (inafct, I don’t have backups in other locations because they were all here). So I can’t recover the date from elsewhere, but hopefully the data for the newest backup (at least)  will still be on the drive, even after the newly copied over windows files…

Can anyone recommend a way to recover the backup file?  Please!!

Phil

Just a note to say that I have now been able to recover a lot of files from the drive, including the majority of the backup files.  I used a program called EASEUS data recovery, which while not having the easiest to use user interface (in fact its a dog) did a great job of scanning the drive for files, and then recovering enough of the filesystem to get sensible names for most  of them - better than others I tried (but given how long it takes to do a deep scan, I only tried a couple of others).  It also has a freeware version to let you recover up to 1Gb of data, but once I had proven it worked, the paid version needed to rescan the drive (another 10+ hours!)

So far it has taken me the best part of 24 hours for drive scanning etc, but the recovered files are now streaming over my network to another computer, and it looks (fingers crossed) like I will recover all of the backups I lost, and most of the other data on the drive.

So, if you are in this situation, don’t despair - it may take time (and money for the recovery software, which once I could see it would work I was happy to pay) but you should be able to recover some, and possibly most, data in the end.