The purchase was in FL. Here's what I found:

http://www.800helpfla.com/lemonlaw.html

Specifically: "The Florida Lemon Law applies to NEW or demonstrator motor vehicles which are sold or leased in the State of Florida. With a few exceptions, a previously titled vehicle (used car) is not covered by the Lemon Law."

So, unless there's something I don't understand (possible), it doesn't sound like lemon laws cover this.

However, I think there's a question regarding whether or not there was fraud or misrepresentation. A call to the AG seems in order, at least to see if the signature of the "As Is" document releases the dealer from any liability. Most AG's won't handle cases on behalf of individuals, but they will forward complaints to a business and keep a copy of the complaint on file. If this dealer has pulled this many times before, this could be the nail in the coffin for the AG to take action.

I also wonder if the fact that the payment was made from out of state helps or hinders the OP. Seems like there are interstate commerce laws that could come into play, even if the FL laws don't. Anyone know?