Combine olive oil, vinegar, garlic and rosemary. Pour half of the marinade into a small bowl, cover and refrigerate. Brush the remaining marinade over the sausages, peppers and onions. Sprinkle with salt and pepper. Discard any remaining marinade.
Coat the grill grate with nonstick spray before starting. Grill over medium heat until sausages are no longer pink, about 12 minutes, and vegetables are crisp-tender, about 8 minutes.
Transfer sausages and vegetables to a cutting surface. Cut sausages into 1/2-in. pieces and peppers into thin strips. Sprinkle each pizza crust with half the mozzarella and Parmesan cheeses. Top each with half the sausage, peppers and onions. Top each crust with half the goat cheese, tomatoes and green onions. Drizzle with the refrigerated marinade.
Place pizzas on baking sheets. Bake at 375° for 8-10 minutes or until cheese melts and crusts are brown. Yield: 2 12-inch pizzas.