Stop using your disk immediately. The best chance of recovery is in the hands of professionals who can help you. Of course you can try pc inspector file recovery and other freewares. But I am highly skeptical about their success rate.
Use Easus recovery like said, used it myself Ninja, and it works fine.
It may take a bit of time to do so set it running and leave it for a bit.
It will recover the lost partitions ect, and any format of the drive will be un done but only if you have not written any more data to the drive since the last format. Its the way it works.
If it finds the old HD data and partition setup of the drive it will create a backup image of it also to re write to the HD so make sure you have lots of free space or, point the saved image of the drive to another HD woith enough free space to store it ok.