Peel and devein shrimp. Bring water to a boil; add shrimp, and cook 3 to 5 minutes or until shrimp are done. Drain well; rinse with cold water. Cut each shrimp in half crosswise, and place in a small bowl.
Combine sour cream and next 5 ingredients, stirring well. Add sour cream mixture to shrimp, and toss gently. Cover and chill thoroughly. Serve on lettuce-lined plates.