1. Heat oil in a large saucepan over medium heat. Add onion and garlic; cook 1 minute. Add rice, stirring to coat; cook 2 minutes. Add wine, and cook, stirring constantly, 2 minutes or until wine is absorbed.
2. Add 1 cup chicken stock, and cook, stirring constantly, until absorbed. Repeat with 1 more cup chicken stock.
3. Stir in remaining 1 cup broth, lobster, shrimp, corn, and leeks; cook 2 minutes. Stir in herbs, tomato, and butter. Season to taste with salt and pepper.