[Three Peaks]

Dimis beat me to it. Budget will drive many of your decisions. If you haven't budgeted $120-150K, forget the Shelby continuation and original cars. Kirkhams will come in a close second in price and are basically the same as the Shelby cars since I believe Shelby still sources their bodies and chassis from them- I'm sure someone will correct me if I'm wrong on that.

Figure out what you want the car for- cruising, track days, all-out racing in a sanctioned series, ability to build it yourself, the camaraderie , or just plain an ego boost. What is important to you- originality, drivability, comfort, etc.... then plan accordingly.

Real1 is partially correct in that the real thing is probably the most accurate, but for about half the money, you can buy a Carbon bodied car by Roger Bollick that is available right now that is about as accurate as a replica can be and not be a CSX car. You've got a long bit of reading to do unless you have a deep checkbook and just want to go out and buy what suits you and drive it.
Keep in mind these cars aren't for everybody so, if you have a chance, sit in a few of different manufacturers and drive a couple if possible to see if this is the right fit for you. The noise, the harsh ride, the lack of creature comforts all can combine to create a hostile atmosphere to the uninformed buyer.

Good luck in your search.

Bob