Bring water to a boil; add shrimp, and cook 3 to 5 minutes or until shrimp turn pink. Drain well; rinse with cold water. Chill. Peel and devein shrimp. Place shrimp in a large shallow bowl. Combine olives and next 8 ingredients; pour over shrimp, tossing gently to combine. Cover and chill 8 hours. Line a serving platter with lettuce; spoon shrimp mixture over lettuce, using a slotted spoon. Garnish with tomato wedges, if desired.