Place red potatoes in small saucepan. Add enough cold water to cover potatoes. Bring to a boil over medium heat; boil 2 minutes. Drain. Remove potatoes from saucepan; drain on paper towels.
Meanwhile, heat oil in large nonstick skillet over high heat. Add shrimp; cook and stir 30 seconds, or until shrimp just start to turn pink. (Shrimp will not be fully cooked.) Remove shrimp from skillet; set aside.
Add sausage and yellow onions to same skillet; stir. Reduce heat to medium-high. Cook and stir 6 minutes, or until sausage and onions are lightly browned. Add red potatoes, sweet potatoes, bell peppers and garlic; cook 6 minutes, or until vegetables are crisp-tender, stirring frequently. Add shrimp and green onions; cook and stir 1 minute, or until shrimp turn pink. Stir in salt and black pepper.