QUOTE(vintage_guitar @ Jan 2 2010, 09:32 AM)

Unless you reformatted your hard disk while installing, your old files are all there. Depending on where you had them on your old OS. (assuming it was windows before) Look around in the windows.OLD folder and your old files in the users folder. You could also just use windows search to save time looking.
Even if the drive is formatted he can still recover the files easily. The sooner you try recovering the better your chances. Use something like EZ Recovery. Good luck.