Read through the pin trading web site on Disney.com. They will tell you all the rules. eBay is a great place to get traders for much cheaper than at the Parks. When you buy them, it's great if you don't like them, that way they are easier to trade away! I have purchased from pinscheap.com as well. I know others on here have also bought from mousepinsonline.com or something like that. I do know that some CM's seem to turn up their noses at the Sedesma pins and all really prefer to get a cloisonne (sp?) pin with the Disney stamp. These pins are made much nicer at you should be able to get them for around 2.50 a pin when you buy a "lot" from eBay.