The lemon law depends on the state. Here in NYS, the lemon law does apply to any and all used cars under 10 years old and with less than 100K miles. It isn't much, but it's something:
b. Written Warranty required; terms. 1. No dealer shall sell or lease a used motor vehicle to a consumer without giving the consumer a written warranty which shall at minimum apply for the following terms:
(a) If the used motor vehicle has thirty-six thousand miles or less, the warranty shall be at minimum ninety days or four thousand miles, whichever comes first.
(b) If the used motor vehicle has more than thirty-six thousand miles, but less than eighty thousand miles, the warranty shall be at minimum sixty days or three thousand miles, whichever comes first.
(c) If the used motor vehicle has eighty thousand miles or more but no more than one hundred thousand miles, the warranty shall be at a minimum thirty days or one thousand miles, whichever comes first.
http://autopedia.com/html/LemonLaw/NewYork_NY_lemonlaw3.html