Race in DMU (Danish Motorcycle Union) under FIM (Federation Internationale de Motocyclisme), which is also the governing body for MotoGP, WSB, AMA, etc.
Not full time, very few racers do that - and for me, like most, the costs are quite substantial. But a man's gotta have his fix
Started by doing a single trackday, like you - had ridden 4-5 years at the time - one hit of the track and I was addicted... Then I bought a track bike, trailer for it, tools, extra rims for rain tires, more tools, more tires, a van to avoid having to tow a trailer, more tools, a travel trailer because I got tired of tenting in the paddock, more tires, more tools, another bike, some tools and yet another bike...

And now I've been talking to some of my friends about buying a bigger van that holds more bikes and has accomodation as well. It never stops...
I decided to start racing after 3 seasons of track and took my race license. More money...
Pros:
- You can not do ANYTHING that is more exciting and fun, with or without clothes...
Cons:
- It's expensive
- You can't quit once you get hooked
- You can get hurt or killled
- It's expensive
In retrospect, I probably should have started doing heroin instead - cheaper and easier to quit....