Window 7, Have no disc.....
What is your end goal here?
If you want it 'formatted' get gParted, boot from that, format the partition into the file system you want and done.
A totally blank HD, and how blank is blank? Then what? dban will do it. http://www.dban.org/
Before I waste any of my time, or before others waste their time with further answers (although they can if they want), there is no more advice to give you without more information from you.
Try this software for your partitioning needs - Free Partition Software - MiniTool Partition Wizard Home Edition
However if you need Windows install media try this link - Download Official Windows 7 SP1 Integrated ISO