Hey, that's a monumental adventure you are talking about IMO lol. Buying a car is stressful enough to me, but add that distance and my stomach is twisting just thinking about it. My first advice is to wait for a local one to become available. Even though this car you are looking at seems like it's the best option, IMO it's better to wait for something 500mi or less away.
With that being said and you are dead set on buying that one, first thing I would do is contact your DMV and find out what you need for temp plates. GA state troopers are no joke and are just waiting to pull you over, nevermind the several other states you have to drive through.
The title should be no prob, they should have a clean one with no liens on it. Here in NY you just fill out the back and both sign it and you submit it to the DMV who mails you a new one in your name. Bill of sale is easy too, just google it and there are several forms to choose from, print it out and bring it along.
But again, my best advice is to wait for something local. There is nothing fun about buying a car 2500mi away IMO, but to each his own lol.