Data Recovery
You didn't want to have to come here. If you had been doing your backups, you'd only be here out of curiosity.
First things first. The more you use a disk, the more the data that will be lost forever. If it's in the Recycle folder, it's easy. Just double click on Recycle Bin and when you find the file, click on it and click on the restore button.
If the disk in question is the system disk ('C:' drive) of the computer that you are using to read this (it's working a little bit), stop immediately, turn the computer off and call me at 781-690-0992.
Often I can remove the hard drive, hook it up to my computer and look for the files you need with a fair chance of recovering them.
When that fails serious data recovery is for experts with very specialized tools and facilities. And it is expensive (4 figure costs are not uncommon). The ones I know a little about are Ontrack, Digitalmedix, and Drive Savers. You will find them easily with a search engine. And there are many more.
Call Corzine IT Consulting at 1-781-690-0992