ap is right: a bike that light is going to be big bucks. Not only for a light frame, but for the most expensive (and lightest) components.

At your height, you can easily ride a "men's" bike. Cervelo makes some nice bikes. The R3 is probably their lightest bike, and outfitted with Dura-Ace will eat at $5700 hole in your wallet. The RS is build with a taller head tube and costs significantly less, though, at $3500 with Ultegra.

You should try a bunch of bikes. Your height puts you at the sweet spot where shops should have a variety of bikes available in a size that's appropriate for you.

Before you buy you should think about how you want to use the bike. Do you want to be able to add a rack, for example?