You don't register guns in NC.
You do have to have a pistol purchase permit, or CHP, and should use a form such as this Google Image Result for http://img.docstoccdn.com/thumb/orig/14609077.png
I made a private purchase, NC to NC and the seller and I completed this form. He confirmed I had a pistol purchase permit or CHP, and we both made copies (cell phone camera photos) of completed document and each other's DL.
This was also for an XD40sc, which is now my favorite gun. Great shooting gun, it's a fist full when you shoot it, but a flawless performer. Get some ammo, some basic pistol lessons (a good CCW class would be a start) and got to the range and shoot it, then shoot it some more.