New to Macs, so can someone describe steps to re-naming an external drive?
While ext HD mounted, select it's icon, hit the enter key which will highlight the name, type in the new name, and hit the enter key again.
Since you're a newcomer to the Mac, see these:
Switching from Windows to Mac OS X,
Basic Tutorials on using a Mac,
Mac 101: Mac Essentials,
Mac OS X keyboard shortcuts,
Anatomy of a Mac,
Switching to Mac Superguide, and
Switching to the Mac: The Missing Manual, Lion Edition.
Additionally, *Texas Mac Man* recommends: