I know you only asked for advice from guys, but I'll tell you what I do. Unfortunately, I'm tearing up a Crossfire, but the Spec Miata class is a very interesting class of racing and a good suggestion.

Before you can "race," you need to learn how to drive on a track. It sounds like you aren't interested in autocross, so road racing is your best option. To develop your skills, you need to find your local tracks and determine in they have High Perfomance Driver's Ed programs. These HPDE's are conducted by Porsche Car Clubs, NASA, BMW's, Viper, Vette and other clubs like 10/10ths Motorsports. They provide instructors, which I suggest you utilize. Before you begin to "race", you need to know what you are doing on the track so you don't trash someone else's really expensive car because you didn't have the experience. These HPDE's are usually two day programs and will cost around $300-400/event. This won't include your hotel stay, food, and tires, etc. If you are not a naturally born racer, then utilize the instructors. NASA has a path to train you to "race." NASA is pretty radical and aggressive; I sure did get some ***** driving with them. Most people are not sponsored. However, there are some amazing set ups, but again, these people just have money.

Now for your car. There are a few things you need to do before you drive a track. Take it from me, I've burned up a lot of brakes (cooked em, fried um real bad.) Minimum mods: metal brake lines, Motul 600 brake fuid, Porterfield racing pads. I've trashed Hawks, EBC and my stocks. Love the Porterfields. Tires: Minimum PS2's, but if you've got money, Michelin Pro Sport Cups for sticking power. Let air out of your tires, because they will gain 4-7 psi/25-30 minute session. These mods, esp. the brakes, are really important.
Other mods as you get money: Harnesses help keep you in your seat and help you relax, but a CG lock on both sides is a minimum. You must have identical restraints for driver and passenger. If you have a Coupe, won't need a roll bar, but you could consider that. Don't even think about racing a roadster as it is hard to meet their demands and requirements. A cold air intake allows people to hear your car and does give a bit more horsepower.
Lower your car. When you do, you'll need to beat out the inside of the tire wells as you'll find your tires to rub a lot. We used KW's and Koni's to lower and tighten suspension. For big brakes for racing, Stop techs are great. But, NOOOOO spacers.
Other equiptment: racing jack, torque wrench to "torque your nuts", tools to change your tires.
If you plan to race your Crossfire, no whining when you get little dings in your car. If you are using a Crossfire, you can't expect it to stay pristine cause you'll be hit by marbles (rubber pellets), mud, oil and all other kinds of crap. If you crash or wreck, your usual insurance won't cover your racing or driver's ed program. So, I have another insurance policy to cover me while doing driver's ed. There are policies for true "racing" also.

I'm sure you know all of this, but sure wish I had someone to tell me what I needed to know to get started. I had to learn the hard way. Of course, being a female was at times helpful because I found that lots of people are willing to help, until you start to pass them on the track. ha Ha.

If you see other people on this forum that are road racers (drivers), go to their tracks and watch them; ride along if you can and see what this culture is all about.

Good luck and I applaud you if you read this entire thread.

Jane