Susan, if you can't get a fish shaped cookie cutter try making one.Use a large vegetable can, and after emptying it, cut the other end off. but have your can opener next to bottom of can so you get a sharp edge.Then shape the can in an oval shape. About 3/4 down can, press in on both sides, and at same time press up on the small part to form what would look like a fish tail. Make sure it isn't one of the newer cans that don't have ridge along bottom. I think you could use a fork to make ridges on cookie to resemble fish scales, and sprinkle with colored sugar before baking. Or you could use colored frosting in a tube to outline the "Fish". Use your best sugar cookie recipe. I have bent a large can in oval shape to use as a large Easter Egg cookie cutter, and decorate with
stripes of colored sugar. Looks very nice.