A really good spot to watch the fireworks at Epcot, is in front of Norway. Amazing unobstructed view, and it's not too far from the exit.
When you walk up to the World Show case, turn left and pass Mexico. Right in front of Norway, it's an amazing view of the fireworks show.
^^ the big globe (Spaceship Earth) is where you enter from. You can see Norway on the map, just head left when you get to the water