We love going to the Tri 'N Run store in downtown historic Winter Garden. It's a small, independently run store and they couldn't be nicer.
For example, if you are looking to purchase new shoes, they'll take measurements and work with you as long as it takes to find the perfect pair. My boyfriend wears size 14 shoes so just finding ones that fit can be a challenge - much less nice ones that are actually comfortable (he suffers from plantar fasciitis). They were willing to call the Brooks manufacturer and have them overnight a larger pair if he had wanted (this was right before Wine & Dine).
They also keep track of your measurements/past purchases in their computer, so if you go back, they already have your basic information and know what to recommend.
What the store lacks in floor space, but they make up for in personal attention. They do attend the expo during Marathon weekend as well.