Bring beer to a boil in a Dutch oven over high heat. Add shrimp; cover and cook 2 minutes. Remove shrimp with a slotted spoon; set aside, and keep warm. Add onion and the next 5 ingredients (onion through garlic) to pan; bring to a boil. Cook, uncovered, 4 minutes. Remove from heat; gradually add oil and lemon juice, stirring constantly with a wire whisk. Add pasta; toss well.
Divide pasta mixture among individual plates; top with shrimp, and sprinkle with parsley.