To prepare stuffing, sauté onions and celery in butter. Add crab meat and shrimp and simmer, uncovered, until shrimp is cooked, about 5 to 8 minutes. Add bread crumbs to thicken mixture. Add salt and red pepper to taste.
Butter two 9 x 13-inch baking dishes. Preheat oven to 350° F. Place 4 trout fillets in each and top with a scoop of stuffing, followed by another trout fillet. Drizzle melted butter on top. Bake for 30 to 40 minutes until fish is done.
While fish is baking, prepare sauce by melting butter and sauteing celery, green onions, onions and garlic. Add shrimp and simmer until pink. Add mushrooms and white wine. Simmer for 3 to 5 minutes. Arrange trout on serving platter and pour sauce over fish. Some of the sauce may be reserved and served in a gravy boat.