While it is true that if you can boil a pot of water, you can cook a Maine lobster - you have to make sure to avoid over or undercooking the lobster. Heres some tips for steaming, boiling and grilling lobster.

Steaming lobster
The ratio of lobsters to the pot is important; a 4-5 gallon pot is ideal for steaming 6-8 pounds of lobster. You should put 2 inches of salted water in the bottom of a large pot with a steaming rack on top of it. Bring the water to a rolling boil over high heat. Put in the live lobsters, one at a time, cover the pot, and start timing. Re-arrange the lobsters halfway through cooking.

Cooking times - (based on the lobster-to-pot ratio mentioned above)
1 pound 10 minutes
1-1/4 pounds 12 minutes
1-1/2 pounds 14 minutes
1-3/4 pounds 16 minutes
2 pounds 18 minutes
2-1/2 pounds 22 minutes
3 pounds 25-30 minutes
5 pounds 40-45 minutes

Boiling lobster
Fill a large pot with water with 3 quarts of water per 1-1/2 to 2 pounds of lobster. Add 1/4 cup of salt for each gallon of water. Bring the water to a boil and put the live lobsters in the pot one at a time, do not cover, and start timing immediately. Stir the lobsters halfway through cooking.

Cooking times - (based on the lobster-to-water ratio mentioned above)
1 pound 8 minutes
1-1/4 pounds 9-10 minutes
1-1/2 pounds 11-12 minutes
1-3/4 pounds 12-13 minutes
2 pounds 15 minutes
2-1/2 pounds 20 minutes
3 pounds 25 minutes
5 pounds 35-40 minutes
Grilling

Pre-boil your lobsters in a large pot of boiling water for 5 minutes then remove the lobsters and plunge into a large bowl of cold water to stop the cooking. Drain the lobsters and store in a refrigerator if you do not plan to grill them right away.

Place a lobster on its back on a cutting board. Then, using a large sharp knife split the lobster down the middle. Remove the black vein from the tail, the tomalley from the body and the sand sac located near the head. You can baste the lobster meat with some oil or butter and then grill the lobsters flesh side down for 5 to 6 minutes, or until the flesh is just beginning to look opaque. Turn the lobsters over, baste with more oil and continue to cook for 4 to 5 minutes longer, or until the lobsters are thoroughly cooked.