Rose-colored glasses

Inspired by The Devil Wears Prada, I'm in the market for a new pair of sunglasses. (Some of the sunglasses Meryl Streep wears are insanely fashionable. I've been wearing the same Wal-Mart pair for about two years. It's time for an upgrade.) I was wondering how to best choose the right pair to fit my face. I did a little digging online, and here are two of the most helpful links I found. I particularly like the first one, because it's helpful to have a visual example of, say, a square face, or an oval face, to help you judge what shape YOUR face is.
1. What shape of face do you have?
2. How to choose flattering frames.

Now, I'm truckin' over to ebay to see what I can find!