All of the parks has a station, some are nicer than others (I thought MGMs was by far the worst for a breast feeding mother). They carry diapers, wipes, medicine, and formula. However, if you need a particular brand plan ahead and bring your own. The items sold are not the cheapest as a poster above mentioned but it is nice to know that the item is there. As I recall EPCOT and MK had the best selections.