Let guests help themselves to these decadent lobster-and-fennel bruschetta.
Place court-bouillon in a large stockpot; cover, and bring to a boil over high heat. Working quickly, plunge 2 to 3 lobsters, depending on size of pot, into the court-bouillon, making sure it completely covers the lobsters. Cover pot; return to a boil. Cook until shells turn red and meat is opaque, about 10 minutes. Using tongs, transfer lobsters to a large platter or baking sheet. Repeat with the remaining lobsters.
Using kitchen scissors, cut off the tip of each lobster claw, and discard; let liquid drain from claw. Twist off tails, and cut down the center to make it easier to remove meat. Using fingers, remove meat from claws, bodies, tails, and legs, and discard shells. Meat can be stored in an airtight container in the refrigerator until ready to use, up to 2 days.
Chop lobster meat into small pieces, about 1/2 inch each. Chop fennel into cubes, about 1/4 inch. In a large bowl, whisk together lemon juice and oil; season with salt and pepper. Toss lobster and fennel in lemon-juice mixture. Adjust seasoning with salt and pepper.
Heat grill to medium. Slice bread in half as if making one large sandwich. Remove some of the insides with your fingers, creating a shallow well. Brush cut side of bread with oil; grill until golden brown and warm. Transfer to a cutting board. Season with salt and pepper.
Spoon lobster mixture over cut side of warm bread. Coarsely chop reserved fennel fronds, and sprinkle over lobster mixture. Use a serrated knife to carefully slice bruschetta into serving pieces. Serve lemon wedges on the side.