Rick- stock standard cars are the best to start with! I ran mine for about 10 track days before touching a thing. You'll have enough to learn without trying to deal with 700hp or stupidly grippy tyres. Having low grip and power will teach you to maximise what you have for fastest corner exit speed which is where it counts.
If you want a cheap lid, go to a motorcycle helmet place like this one -->
http://www.mcas.com.au. Open face from $60, Aus Standards approved and all that. Get someone there to help you pick the right size. And try a few different brands as they all have a slightly different shape. You'll look like an idiot, but walk around to shop for 10mins with the helmet on to test for comfort.
My A050s are on a set of 7and 8 inch wide 15 inch rims I got off highlander. Same ones I had at MTC. Rear tyres have 1 track day left. Fronts have heaps left. Love these tyres. Just killer. GTR rims are now my street wheels with the cheapest available tyres to recoop cost of a050s lol.
Steve, not sure I can do a 9 haha. Probably low or mid 10 would be the limit. Could possibly be done on a set of Hoosiers or slicks but maybe not with semis. Or gimme some NOS!