Hey Scorpios,
Well, to be honest, it is too good to be true. It is not possible to recover a HDD in it's entirity after you have installed another operating system over it. After a HDD and been formatted or repartitioned, the data is still there, but a new File Allocation Table (containing the information of where exactly your files are on the disk) is created. Once you start using that disk again, such as installing a new operating system, the information is being overwritten. Providing the OS is all you have installed so far, the possibility of restoring your other files are quite good.
This is a subject which has been discussed on PCHF many times, for example:
http://www.pchelpforum.com/general-s...xperience.html
EDIT: Marked as Answered.