[Jeff Lee]

As you step in, you'll spend just as much either way or at least the difference will be negligible. The problems with an automatic are you will no doubt need more than one convertor or at the very least you will have to pull it out and send it in for changes you will eventuall learn are needed. At $1200 or so for a quality hand built / custom convertor (at least $900), owning a few can break the bank.
The nice thing about a stick (besides the fun factor, which it is), if you buy the right clutch assembly the first time, it will be all you need and it's infinitially adjustable.
You can buy clutch assemblies from all kinds of sources but there is only one manufacturer that TRULY knows how to provide the right consultation from install to what to do at the track and is almost always just a phone call away. That's Advanced Clutches (note to administrator; I see other sources named on this thread). You can PM me if you need help but it's a google away.
FYI, a good cluch assembly and a great assembly can be three-tenths (or more) apart. So you have to ask yourself, how much would two to three tenths cost if it were up to the engine alone?
You asked about hot-lapping. It's not an issue. In fact, assuming you have the clutch adjusted correctly. It's less of an issue with a stick than an auto as an auto trans retains much more heat (fluid temp) and the a/t trans transmitts more heat back into the engine. I've only made one final in a national and in three days of racing the ET varied only .03 racing morning to late afternoon; three days straight.
As a former a/t racer with all the delay box and auto-shift tricks of the day, I'll say this is the most fun racing I've ever had. Would never go back. But if you don't get the right parts, it will be a major pain in the ***. And as most race parts, it will be more expensive in the long run. Not counting lost rounds.