As far as I know, the only way for sure that you can get chocolate covered strawberries is from room service at the deluxe resorts. You might also find them at Seashore Sweets at the Boardwalk, or Goofy's Candy Company at DTD Marketplace. Not sure about that, though.
You might also be able to order them from the GF bakery, but you can't pick them up and take them somewhere else. Generally, the resort bakeries (with the exception of the Boardwalk Bakery), will only serve cakes or other special-ordered dessert items in one of the resort's restaurants. Except for the Boardwalk, there's no actual 'bakery' that you can go to and buy things. It's just a part of their kitchen.