High temp brake fluid is EXTREMELY crucial. Moreso than brake pads.
Your car was designed to go on the track completely stock. Aside from changing to high temp brake fluid, the most important thing to remember to bring is your learning cap. Absorb the information that people teach you and execute it on the track.
I find that reflecting what I did wrong as I am doing it helps me to remember where I need to implement techniques the instructor told me to work on. Don't shrug this off and build bad habits, be sure to execute and reiterate the correct way of driving on the track, according to your instructor.
Sounds simple, but let me tell you, when you are on the track, there is so much information you are sucking in, it's easy to loose sight of the important picture:
proper technique + safe play = a successful track day!
You will have a blast! Lately, I have been using EBC BlueStuff pads because of the affordability and good street/track performance ($177, shipped for all for wheels - non brembo). Definitely not better than a track-only pad, but it's the closest thing and is technically labeled a "race" pad - Hawk DTC, Raybestos, etc.
You want to be wearing your tires to the line above the PZero lettering
So bring a gauge (as others said) and some air to adjust the air pressure accordingly - I'm using the air pump that came with my Mustang inflator kit.
Almost always I find myself running 5PSI higher in the front than the rear (since the brakes will really warm up the air in the front tires). 45F/40R is usually where I like to start at with a warm tire, and work from there based on tire wear.
One last suggestion:
Study your track you are going to attend and watch in-car videos if you can. Trackpedia is such a valuable resource! http://www.google.com/url?sa=t&rct=j...usXpWJRZptS4cQ