You will find the best lobster preparation I have ever had at Jasper White's Summer Shack in Cambridge, a 15-20 minute drive from the tourist areas of Boston. Beside the Alwife subway station.
Now, I hasten to add that the be all and end all of lobster dishes is the classic, simple, Plain Boiled Lobster served at a shack in Maine with some melted butter and a bag of Humpty Dumpty potato chips. Probably, preceded by a bowl of steamed clams.
But, when you are ready to go to another level, Jasper has a plan. He has created a monstrous, cavernous creation of his idea of the great big clam shack in the sky. A boisterous version of the tiny clam shacks on the Maine coast.
It is big and noisy. The long waits can be maddening. But, this is seafood Mecca for the Chowhound. If you were to have only one more lobster in your life, it would have to be the classic plain boiled, accompanied by just a taste of the ultimate: Jasper's Pan Roast Lobster.
Try the Summer Shack in Cambridge, Jasper White's new place. He is the ultimate lobster and seafood chef in the Boston area. It is very pricey and the atmosphere is "lobster shack chic", but the food will be top-notch.
You also will not be disappointed in any of the Legal Seafoods locations. They are very touristy, so most locals don't go, but the seafood is consistently good and fresh.
I would not necessarily consider Legal "touristy," having been there on more than a few occasions with other more-or-less "locals." (I am assuming that my having lived in the Greater Boston area for >25 years qualifies me to SOME extent as local, albeit not "native.")
I view Legal as expensive, not touristy. Their seafood is generally very good to on-occasion-excellent to sometimes just OK.
BTW as an aside, I was in Sarasota, FL a couple of weeks ago, where Stone Crab is now in season - a most excellent repast, especially when eaten cold with mustard/horseradish sauce.
re: Bruce Smith
I guess I consider the newer Legals (like the one at the aquarium) to be touristy, especialy since I still remember the original one in Cambridge. I think just about all of the places that we used to consider "local" have now been found by tourists and out-of-towners. That's not necessarily a bad thing, just different.