If the disk was formatted and nothing was written to it since then, you have a chance of recovering the data. However, it sounds like the tech support guys formatted the drive and then re-installed the operating system, correct? That's not an unusual reaction from tech support at an educational institution. Unfortunately, it means the data is lost… unless you're willing to spend thousands of dollars on the type of data recovery services that law enforcement agencies use.
If the disk was formatted and nothing was written to it, you can use disk recovery software to restore the original data. There are many commercial options available, but my favorite is the free Linux-based RIP (Recovery If Possible) tool: http://www.tux.org/pub/people/kent-robotti/looplinux/rip/.
This was first published in January 2004