Depending on where you live, there are probably some track day organizations around you who put on trackdays. I'll include some links to resources that list the trackdays in some regions at the end of the post. Once you find out who puts on trackdays, go to their website, pick a date, pay for your spot, and get ready for the day. Read their FAQ and rules (just to make sure that you're ok on bike prep--in case my list was incomplete or too involved) and start counting down the days.
In general, a trackday will cost around $150 for 1 day of riding (depending on the track, the day, the group, etc). Most of the time, every hour of total tracktime is split amongst three groups into 20 minute "sessions"--so for your $150 you get about 160 minutes of track time. To put that into perspective, that's about 80 laps at a long track like Buttonwillow, 110 laps at a shorter track. It's a lot of seat time. I doubt that you could even ride that much (b/c i know i can't)the value for your $ is high.
Looking at the first post, you'll notice that i didn't mention tires. Tires are a huge part of going to the track, and riding in general--and they generally represent the highest consumable cost for this hobby. Your tires need to be in pretty good shape, with lots of tread depth. They do not need to be DOT race tires or slicks, you can run on the track with pilot powers or BT-014's or Metzeler M3's if you want--but again, they shouldn't be worn down and on their last legs.
I won't get into what tires are best, because everyone's preferences are different when it comes to that--but i will suggest that if you have a street bike and want to keep it that way, but also want to ride alot of track that you pick up a spare set of wheels. one for track rubber and one for street rubber. it makes it alot easier on the wallet when you switch to stickier tires that are just for the track.
The most common way to get your bike to the track is to throw it in the back of a pickup truck or cargo van. Riding to the track is never recommended, because you'll have alot of stuff you need to bring with you, like chairs, an ice box, clothes, etc etc--and it probably won't fit in a tank bag. If you don't have access to a truck/van, you can rent a trailer from U-haul or borrow a trailer from somewhere. a small bike trailer is small enough and light enough to be towed by most sedans and SUV's.
Tying down a bike in the back of the bed will be tricky at first, but it'll get easier with practice. A wheel chock makes life much easier for the loader--but they are either expensive or require some work to install. Ratcheting tie-downs also help alot. I won't get into the gritty details--but i will say that i prefer tying down bikes by the triple tree. Canyon dancers always have spotty results for me.
Fitness, Nutrition, and Day of
As the trackday approaches, make sure you start hydrating early. Chances are, it'll be hot, and your 20lb leather suit and helmet are only going to make you sweat more. I like to begin hydration 3 days before the event, continuing to do so throughout the day of. Also, make sure you're eating healthy and get enough rest. Get to the track early, 1 hour before the rider's meeting and setup your space in the paddock. Being rushed and flustered can distract you, and you want to be alert and ready for the morning meeting, where the trackday org/track personnel will discuss important rules with riders.
Track riding is some of the most strenuous physical and mental activities around, so don't take it lightly!
No one expects you to be lightning fast at your first track day. It will take some time to learn the track, and the right line--so basically, don't put so much pressure on yourself to be "Fast." Instead, keep an open mind and soak up as much advice and information as you can. Concentrate on riding safely and smoothly, and the rest will come to you with time.
I strongly suggest that you enroll in a "New Riders" Class, as many track orgs offer something of that kind. They'll go over the basics of cornering, passing, being passed, performance riding and give you pretty personalized feedback throughout the day. This is the FASTEST way to get fast--and is a great resource that you should take advantage of. Also, if you find that you like this whole trackday thing, there are schools that will focus on helping you get faster, like Jason Pridmore's STAR school, or Keith Code's California Superbike School.
What's important is that you ride safely--which doesn't mean slow, necessarily, but within your limits. You can be hurt at the track, as motorcycle riding is a dangerous sport, so don't engage in stupid activities like playing grab-ass with your friends down the front straight. Also, don't think of track days as racing--you're not there to be faster than anyone, and there are no prizes for First Place. You're there to have fun, get faster, and do it in a place that's safer than your local canyon.