Data recovery is simple when you have only deleted a file
If you have recently deleted a file you actually want or if you noticed that a file has been removed from your computer by an uninstall of another program then the data recovery program best suited for your situation is simple Windows recovery software. This is assuming you are on a Windows based PC. If you are on a MAC or Linux driven computer you obviously need specialized software for those applications.
Most Windows data recovery tools will also accommodate some basic file recovery from USB flash drives and camera smart cards. They will not however do a good job with RAW camera files.
See also
Recover deleted files from a crashed hard drive
Microsoft Outlook contact files accidentally erased
Recovering from hard drive
Macintosh HFS+ file recovery
Windows XP restore deleted directory
File Eraser Utility
Undelete Files
NTFS Recovery software
Windows Recovery Software
Empty Recycle Bin Recovery