Place meatballs on a greased rack in a shallow baking pan. Bake, uncovered, at 400 for 12 minutes or until meat is no longer pink. Drain meatballs on paper towels. Reduce heat to 375.
Arrange crescent rolls on a greased 15 inch pizza pan, forming a ring with pointed edge of the pan and wide ends overlapping. Place meatball on each roll; fold point over meatball and tuck under wide end of roll (meat will be visible). Repeat. Bake for 15-20 minutes or until rolls are golden brown.
Transfer to a serving platter. Fill the center of the ring with lettuce, tomatoes, onions, olives, and sour cream.