I had same problem few weeks ago. Do not do the format! You should use one of data restorations programs like GetDataBack for FAT or something similar. (For example: http://www.softpedia.com/get/System/Back-Up-and-Recovery/GetDataBack-For-FAT.shtml)
But you must buy to restore your data. I think I have one freeware program to fix this. I am on notebook now and it is in my table PC. Write me a e-mail and I'll send you it.
And sorry for my english :-)
belansky@mfantasy.cz
Jan Belanský, January 2008