In reply to mmosbey:
Looking at that car, and looking at your intentions, I'm think you'd you'll be happier if you hold a bit and spend a little more money than what that should go for.
Around here $2500-4000 dollars buys you a clean, running, driver. It will need work, but that's invertible unless you want to spend $10k+.
The quick and dirty break down is as such:
Mark 1 cars go to 1967. These all have a 3 synchro transmission. It's more or less a carry over from the MGA. Once you're rolling, you're basically driving a 3 speed. Overdrive was an option, but it's rare and very expensive. 5 speed conversions are possible as is the use of the later transmission. Early Mark 1 cars have pull-handle doors, and a 3-main engine. All of them except the GT have what's know as a banjo axle.
Mark 2 cars start in late 1967. The MGC transmission was adopted. It's larger and the transmission tunnel was changed as a result. First gear is now synchromesh. The GT/MGC axle was adopted for Tourers (The only benefits of this axle are heavier bearing and the ability to withstand a V8)
In '69 the hood(bonnet) was changed to steel. The steel dash ended in '67... None of this cosmetic stuff is important here though. In '70 the grill changed to the recessed black one; this signifies the beginning of the Mark 3. BL markings can now be found. (The downward spiral had begun)
In '74 rubber bumpers happened. These cars are jacked up an inch and half. They have a single 12v battery and the proper engine mounts for a V8 swap. Emissions changes and interior cosmetics evolved (or devolved depending on how you look at it) for the next 6 years.
Rubber bumper cars are the most common with overdrive. It's limited to 4th in these cars, whereas earlier cars operated od on 3rd and 4th. You can bypass the lockout.
I'll get into the engines for you too if you like, but a lot of them are a hodgepodge of parts. A late car, with an early engine, and the suspension put back to what it's supposed to be might be the best for you.
When you look at them check for rust everywhere. Check to see if the lever shocks are leaking. The steering racks can and do go wrong. If the leaf spring bushing are worn, and they probably will be, the rear can get a bit squirmy. The axles are actually offset in the car. Manual brakes are standard until '75. I've never found them inadequate on the road. If you're doing a lot of time in it, you'll probably end up wanting to change the seats. In GRM fashion, Miata is the common answer. Fiero seats work and so do TR6 seats. Anything else will require a bit more creativity on your part.
There's so much more to be said, but I'm not sure what you already know.
Edit: I would have one of the old guys around here would have covered everything by now.