Windows 2000 share file protection

Hi guys. I have a Windows 2000 Advance Server installed for file sharing purpose in my Company. This server function as the Center Storage for around 20 department. Lately i encounter many problem where users mistakenly delete their data and some complaint their data been deleted by other users. The file that deleted will not keep in Rcycle Bin. Is there any tools which i can use to protected the file or to keep the deleted file into another location which can be recover for user immediately rather than recover it from backup tapes?? Thank you