Do the shoes fit

I was thinking of how many miles I had on my New Balance Running shoes. I purchased them in 2003 during my academy. In the academy alone I was running eight miles on Mondays and three too four the rest of the five days. Now as of late I have been running four too six miles a few times a week. I figured that I have at least one thousand running miles if not somewhere over fifteen hundred. Now I am interested in running some half marathons and even throwing in a full one. My hurdle that I am facing is buying shoes that fit and support my feet correctly. So if any of you marathon runners out there reading this have any suggestions, feel free to show your support. Good night.