Preheat oven to 375 degrees. Lightly grease and flour a 10 inch springform pan and set aside.
Cook spaghetti according to package directions; drain. Rinse under cold running water. Return to cooking pot and set aside.
Meanwhile, heat the olive oil in a large skillet over moderate heat for 1 minute. Add the onion and garlic. Cook uncovered until onion is soft; about 5 minutes. Add to the spaghetti and toss.
Mix parsley, lemon juice, basil, oregano, and pepper in a small bowl. Add to the spaghetti and onion mixture; toss well.
In a medium bowl, beat the 2 eggs slightly. Add the ricotta cheese and 1/2 cup parmesean cheese. Add mixture to the spaghetti mixture; stir together.
Place half of the spaghetti mixture in the springform pan; press lightly. Arrange half of the tomato slices on top and sprinkle with half of the mozzerela cheese. Add the other half of the spaghetti mixture and again press lightly. Add the remaining tomato slices to the top and add the remaining mozzerela cheese.
Cover with aluminum foil and bake for 1 hour. Remove the foil and bake for an additional 15 minutes or until the top is brown and bubbly. Cool for 10 minutes then loosen the pie with a thin bladed knife. Remove the springform pan sides then cut the pie into wedges.
Near the end of the baking time, heat the spaghetti sauce. Serve the pie wedges with a ladle of spaghetti sauce and a sprinkle of parmesean cheese.