Lombardi's in New York is pretty awesome. Love Varasano's here in Atlanta. There's also a place here called Antico that won a best pizza in the world contest over in Italy. Need to try that one too.
If you're looking for great places to try, or how to make a great (read world class) pizza at home enjoy this:
http://www.varasanos.com/PizzaRecipe.htm#GreatPizzerias