Well......let's try and make this simple, a per CACC race w/e 6 sessions, approx. 1hr. 40 mins. of track time:

entry fee.....same as above......................240.00
fuel...about 4 gallons Chevron 94.................30.00
brakes....last a year sometimes 2 (drums)......60.00
tires....."could" last all season as cheap as...300.00/set 
rain tires.....never rains here though ........500.00/set

All the peripherals that Jordy spoke of, safety gear, suit etc. FHRD, and so on a one time purchase. Broken parts are relatively inexpensive to purchase.....more serious damage, well let's just say....make sure you're properly prepared "before" you get to the track. This helps a lot for the little things that can easily lead to $$$$ items. There are enough owners of Vees and Fords at any given w/e that can help with any bits and pieces you might generally need to keep going. If it's a catastrophic issue there are plenty of good folks that will help as much as they can.
It's not F-1, but, it's sure a lot of fun
See ya at the track.
Bob 

I think Keith is mistaken about the cost to run pro3...   If you want to run at the front of pro3, specE30, or spec miata you have to bring a cheque book.  I don't think the cheque is any bigger for pro3 vs the other spec series.  As far as the car build cost you can add shocks and a diff over spec Miata but that is typically a one time cost.  The pro3championship car from last year was on a stock style diff and Koni shocks so you don't have to bring the cheque book.  That said....  money helps.... alot!  The part I can't explain is the cost of built pro3 car is around 15-22k right now.  I guess it is supply and demand but the other spec series built cars are typically less.   

As a Pro3 guy and looking at your screen name I have a hard time believing you would be interested in anything other than a Pro3.  We had 43 cars start the nascar race at Portland last year.  We typically get over 20 cars to any one icscc race weekend.  In the pacific north west the is no class that has bigger fields but the Miata is a close second on most race weekends.   

This car looks pretty good for $5800. 
http://www.r3vlimited.com/board/showthread.php?t=280793
While it is not legal for pro3 it would not take much to make it legal.  You could run as is for the novice program and then swap out the parts when you get your senior lic. 

However the others have brought up some solid choices as well.  Miata and FV would be my next choice because of the excellent fields at Mission if you want a spec class.  IP3 if you like the variety of different cars.

Dave

Frank @Drivers Edge.....604.298.5575