You can afford the Dior sunglasses more than the bag, shoes, clothing and other accessories, and believe it or not sunglasses are one of the cheapest and easiest ways to improve your wardrobe and make it more high-end. Unlike most accessories and clothing items, sunglasses are unavoidable, your face is the first thing people see so everyone will notice your shades and base their fashion knowledge of you off that! Think economically and you'll still get the Angelina Jolie look without spending the fortune she does on fabric.
Angelina is wearing Tom Fords in this picture, ad great casual look and one that Jennifer Aniston (also a Brad Pitt honey at one point) also wears. They are a huge brand in Hollywood and something casual enough that regular folk can wear them without looking like wannabes. For men, it's a bit harder because nearly all men look like they are trying to be something they are not in sunglasses, especially designer sunglasses. The best bet is to pick a celebrity you like and buy what they wear and then just play it off like you need to protect your eyes with something! Police, Serengeti and Nike are three of the best brands for non pretentious men.