I just thought in case anyone found it useful, I'd post this.
For a friend of the family, I had reason today to try to recover files that vanished from her camera's SD card.
When I got the card home, and put it in my reader, there were only 32 images visible in explorer on the card in Windows.
I looked for a card recovery program, thinking if she wanted the photos badly, perhaps a cheap one was available,
and found one called Digicam Photo Recovery, which did the job rather well, and rather quickly.
The program is FREEWARE, and available here: http://www.aliensign.com/
I was able to recover 127 images from the card, including the 32 that were still visible,
one of which dated back as far as 2006, which I am assured is the correct date for that photo!