Steam the broccoli florets, covered, 4 minutes or until crisp-tender, and drain. Rinse under cold running water; drain. Combine the broccoli, bell pepper, and lobster in a large bowl; toss well.
Combine the yogurt and next 7 ingredients in a bowl, and stir well. Add to broccoli mixture, and toss well. Serve on lettuce-lined plates. Garnish with fresh dillweed, if desired.
Note: Steamed lobster meat is available in some supermarkets. Or you can cook whole lobsters: Fill an 8-quart stockpot two-thirds full with water. Add 2 tablespoons salt, and bring water to a boil.
Plunge lobsters, one at a time, headfirst into water; return to a boil. Cover, reduce heat, and simmer for 8 minutes. Remove from water, and let cool. Crack shells, and remove lobster meat.