Yes there is a little booth by the American Pavilion that sells them. They have different kinds, some just with sugar, and others with fruit and different toppings. Definitely try it!!!
It is fabulously tasty and totally not on a healthy diet! That is why the only time we have it is at WDW; it (sadly!!!! ) has little place in the - sigh...... - real world. Try it, though and you will be in heaven!
It is called a funnel cake because they take yellow cake batter and drizzle it into a deep fryer through a funnel. It is ribbons of fried batter in a circular shape. They then dust it with powdered sugar or top it with fruit (and powdered sugar). They sell them at Epcot and the water parks.