I thank you for the question. I was planning to make this entry long time ago.
I can give you a very easy method to recover the data back (if it is still not too late).
Just download Recuva and run it.
Let it do the work for you. This software is pretty much easy and user-friendly. It's free too. Once you run it, you'll understand how it works.
And I really really recommend this software. I'm using it and I am satisfied with it, so I don't go and search for other softwares This one is good enough to sit in your system.
There are also some other softwares which are very helpful but I am too lazy to google for them.
P/S: Probably I should make another entry about recovering data from your damaged/crash hard disk. Yep... I should... I think, but later (or no at all)