Good Athletic Shoe Stores?

[hummingwolf]

I don't know if this topic is of general interest here, but it is DC-related and rather important to me:

Can any of you recommend a good athletic shoe store in the DC area, preferably one near a Metro station? I cannot drive for health reasons (seizures), so walking is not only the easiest form of exercise for me, it's also my main mode of transportation. Lately I have been having the worst luck buying shoes that fit decently without causing pain, blisters, or bleeding. If any of you know of any stores around here with knowledgeable, helpful staff who can help an increasingly desperate pedestrian find good footwear, please let me know!