Lamb Necks are useful for stews and the like. The meat is fairly dark and flavorful, and there is little fat. The photo specimens were 4 inches long, 2-1/2 inches high and 3 inches across and weighed 1 pound each. Each of these chunks contained two neck bones.
Keep in mind, if using an English recipe that uses the traditional English lamb cuts "neck" means something quite different. See the English Lamb Chart.
More on Lamb / Mutton Cuts.
Buying: These can be found in markets serving communities from countries that use a lot of lamb: Turkey, Armenia, Middle East, North Africa, Pakistan, etc.
Cooking: Neck meat is well exercised so it's both flavorful and tough. Given the complexity of the bones the practical method for recovering this meat is to simmer for two hours, after which it can be easily removed from the bones with a fork.
Yield: A one pound neck piece (two bones) will yield about 10 ounces of meat (63%). Of course to fully recover this meat, the neck pieces need to be simmered about 2 hours so the meat can be pulled off cleanly. After simmering the cooked meat will weigh abotut 5-1/2 ounces (34%).