Just go to the track. High Performance Driver Education.
I constantly have conversations with people about the track hobby. The barrier of entry is actually very small but yes, it can be intimidating to get out there for your first time. Depending on where you are located at the in the country there are a huge number of organizations that put on track days that you can attend. And honestly all you really need is a car that is in good mechanical condition with usable tires and brake pads. So many of these conversations involve the person waiting to do this or that to their car in order to be "ready" for the track. This is complete crap. Modern day automobiles are pretty impressive. You can take a stock car made within the last 20 years in good mechanical condition and flog it for hours on end on a race track with not much to worry about.
With that being said think of all the money, time and effort you will save by just taking the car you have now, as it sits, to the track. This is especially true if you are new to the hobby but the most important aspect of any car on a race track is the person behind the wheel. You can take 3 drivers and put them in the same car and get 3 drastically different results simply due to the driver. Seat time and understanding the way the cars work on track will far outweigh any specific modification that you want to do to your vehicle. After your first 2-3 weekends you will start to understand what, if any, modifications you actually need to perform in order for the car to work better on the race track. Most of the time those changes are very simple things such as a better set of tires and brake pads. Still using the Keep It Simple Stupid mentality working on you, the driver will continue to outpace any modification that you perform to the vehicle.
I, fortunately have been doing this for quite a few years now and have a better understanding of the hobby and like to try and pass on some words of advice to those getting interested in taking their cars to the race track. All it takes is 1 session and you will be hooked. I try and practice what I preach. The IPGparts.com BRZ is about as simple as it can be. I did the basics to the car which included tires, brakes and coilovers but power wise the car is completely stock as delivered by Subaru as my goal is to run every minute of every session available to me during any event so reliability far outweighs any modification that I may perform. After 21 track days in the BRZ I am just now getting to the point where I am considering making a change to the vehicle. Stock'ish cars are pretty amazing what they are capable of.
Another byproduct of the track hobby is how much better of a driver it makes you on the street. An important component of being on a race track is situational awareness. You need to know what other cars are around you, are they faster, slower? You need to pay attention to the corner workers and any flags they may be displaying to give you information on track conditions. You need to constantly understand what is going on around you all while trying to be as quick as possible around the race track. This situational awareness spills over into every day activities. Combined with understanding your car and the way it reacts in high speed, evasive maneuver scenarios and what may be the limit of traction or braking is the added bonus to High Performance Driving Education.
So that is what I am telling you. Keep It Simple Stupid. Get the car prepped and go to the track. Working on yourself as a driver is the best modification you can do and it surprisingly also saves you a lot of money during the process. -- James Innes