I would say any of the resorts, but you can pin trade with any cast member. I noticed I have found some rare pins looking and asking the CMs at the resorts to see their lanyard. Also the resorts have the pin boards as well. My last trip I was able to score an Adventurer's Club pin and I was pretty excited. EPCOT also has a pin station right by the fountain in front of the electic umbrella ( Im not too sure of the other parks).