That is awesome. My first track day was 1 week before yours at Thunderbolt. I am also hooked and I am sad that I am hooked because it is an expensive sport.
Here is my second session. No instructor-They did not have enough for everyone so we shared instructors between sessions. My goPro ran out of memory so I did not record 3rd and 4th sessions.
http://www.youtube.com/watch?v=ZHGHDFmS_Lg
I shaved off at least 33 seconds from my first lap in the 1st session to the last recorded lap in my 2nd session. The instructors instructions made a huge difference. I had normal street tires and oem brakes. Just exhaust system, intake, and eibach lowering springs.
I was also trapping 105-115mph at the end of the straight and that octopus was annoying. Always messes me up. Almost went offroad at one point from understeer.
Let me know when you go to more events. I will come along. And like you said, it is an eye-opening experience. I was so surprised by what my car was capable of and I know it can do so much better in the hands of the stig. haha.