I'm confused. Are you actually trying to recover the files that were on the drive before you reformatted it? If so, you can stop trying, because it's not going to happen unless you spend about $1,500 at DataDoctors or some other specialized service. Reformat means completely erase, then reallocate the blocks of the drive for new use–which pretty much kills any chance of file recovery.

If you're simply trying to repartition the drive, you should be able to use Apple's Disk Utility app to completely reformat the drive and re-partition it. Notice I didn't say "restore." You aren't going to be able to restore anything, because there's nothing there to restore.
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