Well I plan to stay in Georgia, so hopefully the HOPE scholarship, or something of the like, will still be in effect by the time I have college-age kids. (As long as you keep a 3.0, public in-state tuition is paid.) If that isn't an option, I'd help them out as long as they were in college. I'm not helping out a deadbeat. lol. That sounds awful.
As for a car, my mom bought me a car at 16, a $4000 MX-6. I don't see any harm in buying your child a car, but I don't see spending more than 20 grand on something they have a huge likelihood of trashing, and they need to learn the value of money.