So you're in disk management and you can't see any drive there? Even after you right click and rescan?
You could always try diskpart and clean the drive.
NOTE PLEASE MAKE SURE YOU SELECT THE CORRECT DISK, I'M NOT GOING TO BE RESPONSIBLE FOR NUKING YOUR DATA.
Also note I am writing this off the top of my head..
Fire up an elevated command prompt.
Type (where [return] means press return) :
Diskpart [return]
List disk [return]
(You should now see all attached drives with a corresponding #, if it doesn't show up then it's not attached)
Sel disk # (where # is the disk number) [return]
(NOW BE REALLY SURE YOUVE SELECTED THE CORRECT DISK AS THE NEXT STEP WILL NUKE IT)
Clean [return]
You may be asked to confirm.
Go back into disk management and rescan, it should show as an un-initialised drive and prompt you accordingly.