For the Clam Broth: Heat olive oil in medium saucepan over medium heat. Add the onions, garlic, carrots and celery and cook until soft. Add the white wine and cook until reduced to 1/4 cup. Add the clam juice and cook until reduced to 3 cups. Add the tomatoes, season with salt and pepper and cook for 5 minutes. Place mixture in a blender and blend until smooth. Strain into a clean bowl.
For the Grilled Sausages: Preheat grill pan over high heat. Grill sausages until cooked through and golden brown and crusty on outside. Remove, let rest and slice on bias into 1-inch pieces.
For the Clams and the Broth: Heat olive oil in large saucepan. Add shallots and cook until soft. Add tomato/clam broth and bring to a simmer. Add the clams, cover and let cook until all have opened. Remove clams to a bowl with a slotted spoon. Increase the heat to high and cook the broth for 10 minutes, until slightly thickened. Add the butter, salt and pepper and parsley. Place 6 clams and a few pieces of each of the sausage in a bowl. Ladle over the clam broth and top with some of the relish. Serve with French bread.
For the Sweet Onion and Grilled Pepper Relish: Combine all ingredients in a medium bowl and season with salt and pepper to taste.