Running shoes are good for 600 miles or so. After that point, they need to be replaced. Most runners know which shoes work best for them and simply shop around for the best price on that model. Specialized running shops will perform a gait analysis on an in-store treadmill to match you to a shoe based on your arch, gait and other factors. If you have the time and patience, it is worth it, especially if you are prone to injury.
As it’s time for a new pair of shoes, I’ve been shopping around recently. I found a great deal at Jack Rabbit in Union Square…30% off last year’s model. If you know what you’re looking for and want to save some money, check out Jack Rabbit and ask if they have last year’s model to take advantage of the discounted price. The only catch is that you cannot return them so be sure it’s a model that’s right for you and the correct size.