The problem may be you have rewritten the partition table by creating a new partition - even tho. you have not formatted it.
If you rt click it and don't get the Undelete option , you will need to delete it again , then Undelete.
It may only only reconstruct the last partition you just created - if that is the case , then nothing will be able to do it. Worth a try.
Otherwise there is something else you could try. Unless you are going to send it to a specialist recovery firm , you could remake the partition , do a quick format and see what these two can recover after a quick format - can't guarantee what you will get back tho.
Hope it helps