If the file was overwritten it is gone. You could try other recovery apps but not one I know of will recover from an overwritten file. Even http://www.drivesavers.com should not be able to recover that one.
There's a lesson here.
I acidentily deleted one photo on my camera. (canon IXUS 8015)
I downloaded the software 'Icare Undelte (free)'.
I tried to recover the one photo deleted by the camera software itself.
I could 'undelete' 50 pictures from my SD card, wich I had already uploaded with Picasa (and deleted). Even some that were 'formatted' came back.
But not the one file - 'Icare Undelete' sees the filename but gives no 'Preview' or 'Save' option.
I also tried the software 'SD cardrecovery' which gave the file status 'overwritten'. Although I did not make any pictures after the delete accident.
I tried software 'Recuva' with the same result.
So three recover and undelete programs that can not undelete my photo. The SD card is 'SacnDisk Ultra II' type 4. Has any one any clou.