let me help you guys out..
you don't have to do anything to your car.. seriously.. especially if you are a rookie.. a stock car will do just fine (except maybe stock re92).. the goal is to learn how to drive your car.. =) just make sure you have some fresh oil in your engine..
but if you HAVE to do some mod, i would suggest tires first.. if you have money, go for R-compounds.. if you are tight on budget, grab some summer tires.. second would be some shocks/springs combo or coilovers.. then brakes (pads, lines, fluid)..
imo, you can always try to brake earlier.. hence the need for serious brake upgrade would not be necessary for starter..
if you have to worry about insurance, maybe you should think twice.. if you want to go out there and push the limit and expect ppl to cover your ass when you crash your car, you are nuts.. lol.. so either take it easy and have fun or pay to play..