In a large skillet over medium-high heat, saute the ground turkey for 5 to 10 minutes, or until browned. Drain the turkey, stir in the tomato sauce and sugar, and set aside. In a medium bowl, combine the sour cream and cream cheese. Mix well and set aside.
Cook noodles according to package directions. Place them into a 9x13-inch baking dish, then layer the turkey mixture over the noodles. Then layer the sour cream mixture over the turkey, and top with cheese.
Bake at 350 degrees F (175 degrees C) for 20 to 35 minutes, or until cheese is melted and bubbly.