Formatted Drive

Ok heres my problem...I have my hard drive set up with two partitions...c drive and x drive. I used X to put all my files and installers and things like that on there. Windows started screwing up and I decided to reformat C to get it back to working correctly. When I was reformatting and installing windows...it messed up and combined both my C and X drive together and lost all of my stuff from X. Do you guys know what software I can use to get my files and things back? Thanks a lot. Freeware is better if possible.