A couple of things. If you are going to stay "in town" - you are probably too late for reservations this year.
I took my travel trailer along, but missed one VERY key thing. It is VERY (very,very,very very etc) HOT there and I did not have enuff brains to bring a genny for powering the A/C in my TT. Luckily, the temps dropped to the 95-100 range at night
If you are sleeping in the van, under your pickup, in a motorhome (a moho) a travel trailer or in a tent - you can stay for free. Just park on the salt, near the bend (where the access road curves) and there you are. Bring EVERYTHING you will need, as you will be camping in the "basic unserviced camping area". In the case of my trailer, we had everything needed including water and toilet and shower a stove, a microwave and a fridge to keep the bottled water cold. We froze a dozen bottles every night and cooled another dozen to take with us to the scene of the action every day. With the frozen ones plus the cold ones in the picnic cooler, we were OK for hydration. (If we had brought a generator for the trailer's A/C, it would have been perfect!
Take a LOT of "SPF a million" sunscreen and wear long sleeves and long pants. The stories of the sun reflecting off the salt and burning your "don't touch'ems" are true for those in shorts
Welding glasses shade 6 -9 are about right for eye protection. A wide-brimmed hat is mandatory.
You can walk around in the pits, most teams are VERY friendly, you can stop & chat with 'em. My son & I chatted with the Poteet & Main crew and passed wrenches when they were in a thrash from burned pistons due to a screed up fuel line. We stopped and chatted with the university team running an electric car, and with various other teams running all sorts of different vehicles from a Renault with a Hybusa engine to a team with a huge Kenworth running V16 Diesel power.
At the start line, you can (if you don't make a jerk of yourself) walk among the cars waiting in line for their turn, and at worst you stand about 3 -4 feet away from them.
Downtrack, you are about a mile or so from the cars as they go past, for safety reasons - if someone cranking 300 plus gets off the "track" and outta control, you gotta be LONG ways away if you are going to live through it!
Despite the "million miles per hour" speeds, the whole thing is very laid back, very friendly. Teams loan each other tools, help each other etc.
That fact is most notable at the start line. Instead of the Christmas tree or the frantic waving of a green flag, there is a guy on the radio who stands in front of your car when you are next up, listens to his head set for messages about when the last car has finished its run and the track is now clear and then he turns to you and double-checks that all your latches & catches are done up, your safety pin is pulled on your chute and then, with an "After you" sort of gesture, steps aside. "The track is yours for the next 4 minutes"
Your push car starts up and takes you out and up to 40 (or 50 or 75 or 100 MPH) and you get on it and go, while your push car drops back and peels off to the left to meet you down track and pull you back to the pits. Maybe you don't use a push car and just drive away from the start line. If you're on a bike maybe someone pushes you while running for the first 20 feet.
Oh yeah. Take an AM radio, and FM radio and a CB radio along for listening to track announcements, track news and for listening to communications between officials and teams. ("Um this is car XXX - I just pulled off to the right at mile marker 4 - my motor let go all over the track - some pieces came right through my hood. You better get a safety clean-up crew out there before you let the next car down. Hey Frank - I'm back just past mile 4 with only about half an engine left in it - wanna bring the trailer and come get me?" ) (That's a direct quote of one racer's call on CB radio)
There are TWO tracks - the long course for the "big boys & girls" and the short course for vehicles running less than 200
There are snack stands, ice creams stands, bottled water sellers, sunglasses sellers (expen$ive!) and rental porta-johns around, as well as a place to stop and wash all the salt off your ride at the end of the day. Admission is quite reasonably priced and buying a program and a rule book is highly advised.