I second eck - go to a place that specializes in running shoes. The running store in gainesville, va is fantastic. They videotape you running on their treadmill to identify how you step, then get shoes to provide the right level of support. It takes a while, but I love the shoes they gave me and it only costs about ten bucks more than Dicks.
Yeah, do not go to Dicks, go to a running store. I go to a place in Reston Town Center that videoed my horrendously goofy running form and recommended me a pair.
Also, those minimalist running shoes are not for everyone. I would injure my feet and legs if I tried to run in them.