some additional info:
You'll need a helmet. Snell SA2000 will work. If buying new, I recommend SA2005. If you have a motorcycle helmet (snell M2000 or newer), check with NASA to make sure its allowed at Putnam Park (track rule says no, but I hear NASA has an exception? its a gray area, for sure).
Entry fee for the weekend should be around $325. This is two days of high performance driving, about 80 minutes of track time per day. If this is your first event, register for HPDE 1 and you'll get classroom time and an in-car instructor assigned all weekend.
Vehicle should be in excellent mechanical shape (up-to-date maintenance, etc) and brakes should be the #1 area to focus in if you want to be best prepared. Don't worry about adding any horsepower, you probably have too much already. Cooling, reliability, and safety are always a great idea. Brake pads should have atleast 50% material left, preferrably a track or race compound. Need fresh brake fluid, flush with something good closer to the event.
I recommend booking your hotel early and registering as soon as its available (will be a thread bump once registration opens). This event fills fast!!
This is a great opportunity to develop some disciplined driving skills, and experience your vehicle at its limits in a safer setting than the streets. Hone your skills, have a blast, and be safe! This weekend will be a riot, you don't want to miss it.