I jsut got back from almost 2 weeks in Spain and discovered razor clams. Oh. My. They are nutty, sweet, firm, toothsome--are they just a Med thing? I have never seen them in the US. Do I need to finagle another trip to Spain or can I satisfy myself here?
FWIW, they are mentioned in Joy of Cooking. I don't remember seeing them in the SFBA where a large amount and variety of fish and shellfish are available, but then I don't buy fish very often. If you're near a coast and/or a decent fishmonger, it might be worth a phone call. For mildly unusual stuff like that, a visit to Chinatown is usually my fallback suggestion.
The common razor clam species on the US Atlantic coast is Ensis directus, simply called "razor clam" or sometimes "jacknife clam." They range from Canada to the Carolinas in shallow water. I've encountered them occasionally while digging for the more common edible clam species, but I've never seen them in large quantities. I seem to recall seeing them in seafood markets at times, but I can't remember specifically where or when. They're supposed to be edible and have been described as pretty tasty, but I've never eaten one so can't comment on that.
ETA: I just did a little poking around online, and apparently there's a Pacific razor clam species as well. It's not particularly closely related to the Atlantic species, but is also said to be edible.
Not sure where you are located, but you can definitely find them in Chinatowns. They are indeed delicious.
In the late 60's I lived in Seattle and we would go razor clam digging on the Pacific coast (not in Puget Sound, but on the wide sandy surf washed beaches around Grey's Harbor.
At low tide the clam beds are exposed and razor clams can be identified by a characteristically shaped hole they make in the sand with their siphon. You dig them with a "clam gun" which is much the same thing as a bulb planter. It cuts a cylinder of wet sand which you lift up quickly and break apart to find a single clam. This fishery has been greatly depleted since those days. I am under the impression that commercial harvest is not permitted and that even the "sport season" has been cancelled often due to overharvest or some other source of population depletion. Maybe someone from the Pacific Northwest can fill us in on the details. They were, when I ate them, the most delicious clams I ever ate-nutty, juicy, slightly chewy like squid, but more flavorful. They can dig very fast in the sand to elude you and trying to extract an escaping razor clam by outdigging it can be great sport with enough beer and sunshine to go along.
I grew up in Oregon and ate razor clams often as a child - particularly on trips to the coast. The standard prep was breading and pan frying. Yum.
More recently I lived in Long Beach WA, where a lot of razor clam digging goes on, but not commercially. The razor clams that are available in coastal NW restaurants are now from Alaska I was told. I have no idea how widely they are distributed.
I eat razor clams whenever possible in chinatown (Montreal) - that is whenever they have them. As you know, they are simply delicious. They are also sold fresh in the chinatown fish markets, usually tied in a bunch with green (?) twine, but not always available.
So as other posters mentioned, perhaps check your local chinatown, if possible.
I also purchased canned razor clams from "Robinson Crusoe" which are from Chili. Though tastier than your run of the mill canned surf clams, they do not measure up to fresh.
You can see them here
(click on canned seafood, then molluscs, then pacific razer clams....I dunno how to get that specific page...)