Help Please accidentally deleted drive letter

Hi in a serious amount of trouble was trying to fix a usb drive with some software called bootice, and i accidentally deleted my drive letter on my c drive as i wasnt watching what i was doing. My os is windows 7 can and now as it has no drive letter it obviously doesn't boot up. Can anyone point me in the right direction please to fix my problem?
I know im an idiot but i really need some help please..
Thanks:Mad2: