This is by no means an exhaustive list, just places I remember my kids getting them...
Magic Kingdom - the quick service place under the Astro Orbiter in Tomorrowland.
Epcot - the "Outpost" between China and Germany in the World Showcase
Studios - the stand across from Toy Story Mania and another near the lake, kind of across from Hollywood & Vine
Animal Kingdom - a stand in Dinoland, in the carnival-y area