If you do buy new shoes, never buy this year's edition. Try them on at a store until you find the ones you want, then go online and buy the previous year, you'll save at least 20%. The differences between years are negligible unless it was a total redesign of the line.
Also, be wary of any store that recommends you buy some $150 "motion control" shoe. There has been a lot of research recently that indicates motion control shoes don't help prevent injuries at all, and may actually increase you chance of injury because of how they change your natural stride. Better to get some good insoles or orthotics and slap them in a plain old cushion shoe than run in some heavy stability clogs.