I deleted a 'I' drive from one of my hard drives, but it deleted my main partition, how can i recover it? It says it has 450 unallocated space. It took like 10 secs to work so i dont think it formatted it.
Use TestDisk to recover a deleted partition. I would need to know more specifics such as your OS (Win/linux/os x) and what type of partition table(MBR/GPT) and file system(FAT/NTFS/HFS+/EXT) to provide more detailed steps for how to use the program. The guides on the website are pretty straightforward and the menus are pretty simple so you can probably figure out how to use testdisk on your own.
Also, stop using the drive with the partition you are trying to recover until you are finished fixing everything. Use a different drive or some kind of removable storage to install testdisk on and perform the recovery.
Fix for Windows 7:
Create a bootable USB stick or CD that contains testdisk on it. It is very popular and thus is included on many distributions including Knoppix, Ultimate Boot CD (UBCD), and Trinity Rescue Kit (TRK). Once booted, open a terminal and determine which the path to the hard drive you want to recover.
You can also use EaseUS Partition Recovery, supports
Video demonstration: http://www.youtube.com/watch?v=fhd2JP8jomA
Article: NFTS partition recovery from EaseUS.