Seconded and I would also like to know if there are novice leagues or races that do not require die hard enthusiasts.
So here is how it works, you must purchase a subscription to be able to race with the minimum content. Subscriptions cost about $10 a month, but they always have deals so I think you can race for your first 3 months for a total of $10. They have yearly deals where you can get a year's subsription for $49 or two years for $99 I think.
There is also a chance to recoup some of that by racing in what they call "offical" races. I will explain more later, but just remember that you can collect up to 10 dollars per season, for a total of $40 dollars per year to spend on the service, or cars, or tracks, etc.
So I'm sure the iracing website describes what you get with minum content so go over there and you can see all the tracks and cars you get. There are cars and tracks that are not part of the minimum content, i.e. Daytona. You must purchase the track in order to race on it. Tracks typically go for about $15. The cool cars are the same way. You must purchase the cars to use and they run about $10. Once you purchase them you never have to buy them again. There is a 10% discount if you buy 3 items together, 20% discount if you buy 6 items together, and I think 25% if you decide to buy everything at the same time, (no one does this because it would cost a boatload since there is so much content now).
The bottomline is that if you join the service you will start out driving the street stock or classic Ford Midget car until you can get the appropriate license to race the other cars.
The service is broken down into two types of racing, oval and road. You get two ratings for each type of racing, one is called SR for safety rating, and one is called iR for iRating. The SR is used as a license. The higher your license the more cars you are able to race with. This means that you can buy any car including the NASCAR Sprint Cup car, but you can't race it until you have an A license. You can still practice with it and test with it, but you can't join an official race. The SR starts with a Rookie license (which is where all new subscribers start) and it goes up to D, then C, B, A, etc. There are also Pro Licenses if you get really good and race a lot.
The iRating is just a simple evaluation of how you have done in your past races. It starts at 1000 points and goes as high as you can get it. Dale Earnhardt Jr. is somewhere in the 9k or 10k range. Basically, if you finish an "official" race in the top half then your rating will go up. If you win the race it might go up by 100 points, if you come in last, it might go down 100 points and if you finish 5 out of 10, you might gain 10 points.
More to come...