They are all very good cameras, but are designed with an advanced amateur in mind. They have extensive controls so a knowledgeable photographer can optimize settings for exposure and creative control. If you have no experience with a DSLR, or even PASM, such cameras won't take better photos than less-expensive DSLR's.
As far as lenses are concerned, the "kit" lenses are decent optically, but on the cheap side from a construction standpoint. Lenses that try to cover a lot of focal range, like 18-200mm, are more convenient than good. 200mm is probably not even enough reach for what you want. You would be better served with the kit lens, plus a second telephoto zoom lens.
I have at best amateur skills, I am attending the Indy 500 and would like to know what camera and lens would be the best for taking action of racing and also pit pictures? I have looked at Canon 7D, Sony a850, Nikon D7000 all with 18-135 or 18-200mm lenses any suggestions?