Combine dill, garlic, half of the oil, lime, lemon and orange juices in a small bowl. Season to taste. Place salmon in a shallow non-metallic container and pour over the dill mixture. Cover and refrigerate for 2 hours.
Meanwhile, segment lemon, orange and lime over a bowl to collect all of the juices. Stir in the tomatoes, balsamic and remaining oil.
Place drained salmon fillets, skin-side down, on a heated barbecue or grill pan. Cook, covered, for 3 minutes each side or until the skin is crisp and salmon is cooked as desired.
Serve salmon on lettuce leaves and topped with citrus and tomato mixture. Drizzle with extra balsamic and serve with crusty bread, if desired.