What you can do, is simply choose from a CAMS affiliated club to be a member of. Choose yor favourite, coz you can go for any track day held by any CAMS-affiliated club. And pay no more than the track day fee. Imagine one club membership that allows you to play at all golf courses.
Myself, am with PIARC. And they are holding an event called Island Magic, 2 days of track( attend 1 or both) on the 29th and 30th of Nov. So simply download the entry form and post it in. The important things u need are,
1) Extinguisher that complies with CAMS regulations (Metal bracket, etc)
2) Secondary bonnet restraint device( any strap or belt will do)
3) Metal valve caps
4) Helmet (ANSI approved)
5) make sure your car is in a roadworthy condition,ie: no drips leaks, etc.
6) And some clubs are strict about a 75dB limit at 30m driveby. ( Most cars will be under that)
I think I mentioned the most important ones to get started.
Costs,
Club membership: $30-$50
Cams L2S( Level 2S) : $90
Track day fee: $90-$120
Hence, to go on the track the very first time, you'll need about $240. Thereafter, you only pay for the track day.
Hope this helps.
Cheers
Dex