CDRLabs.com

After a reformat, I lost all files and programs that were previously installed. Normally, after a reformat, I would go to Documents and Settings to search for files under the username before the reformat. This time after the reformat, there was only one user instead of the previous users; My computer was as if I'd just taken it out the Box brand new. Is there anything that I can do to retrieve those lost files?

Nope, afaik you are screwed. Reformating wipes all info from the drive. You may be able to run some type of recovery program that scans your HD for files that are still there with no link, but I have my doubts about it working!

what you have done in the past is not reformat the hard drive, but rather reinstall windows 'on top' of the current installation. effectively Windows is re-installed (well, not exactly) but all the files previously on the computer should still be there, including the old users' Documents and Settings.

this time, you apparently did re-format the partition.
barring using special recovery software like redk said, your files are gone