A recent visit turned up six varieties of oysters on the half-shell--from Black Bay, Louisiana, from Wellfleet on Cape Cod, from Malpeque Bay and Salt Aire Bay on Prince Edward Island, from Prudence Bay in Rhode Island, and from Parramour Bay in Virginia. Given the crowds of avid oyster eaters, you're assured good turnover and the freshest possible servings of the ocean's little wonders. Add a bowl of clam chowder, some steamed mussels, a couple of crab cakes, and a lobster, and you'll swear that's not Lake Minnetonka out the window--it's the Atlantic.