In an oval or 9 x 13" baking dish, defrost the meatballs in the microwave according to package instructions.
To the defrosted meatballs add the tortellini, marinara sauce, and diced tomatoes. Toss together well to coat the pasta and meatballs completely.
In a small bowl, stir together the ricotta cheese, Italian herbs, and garlic salt. Drop small dollops of the ricotta cheese mixture evenly over the top of the pasta. Top the pasta evenly with the shredded mozzarella cheese.
Bake at 350 for 30-35 minutes or until the cheese is completely melted. Cool for 5-10 minutes before serving. Top each serving with shredded Parmesan cheese, if desired.