So true Jennyma. Canned clams are so nasty for true clam chowder. I don't use flour in mine. I prefer to add extra potatoes and mash them to thicken it. I also don't like mine too thick. And I use heavy cream. It really add a creaminess that you just can't get any other way.
Fresh clams are the only way to go. Take it from an old New Englander. The definitive expert on New England chowders though is Jasper White. He uses only salt pork in his chowders and seafood stews. And no flour. He thickens his chowders the same as I do.
You should be able to buy clams in the shell at your supermarket. When you go to steam them, make sure every one is closed. Tap any open ones and if the fail to close, get rid of it. It is already dead. Place them in a pot with just a couple of inches of water. Place a lid on the pot and steam them from simmering point for only a couple of minutes or until all the clams are open. Once opened, they are cooked. If you cook them for too long, they will be very tough. If any fail to open, get rid of that one. Bad one. You don't want to take a chance on eating any dead or bad clams. You will regret it.
As soon as all the clams are open, remove from heat and remove clams from the shell trying to catch any liquid in the shells. Strain the broth in the pot through a cheese cloth or coffee filter. I happen to like the whole clam. Including the intestinal tract. Some folks don't. If you are of the former, then soak the clams in heavily salted water. In fresh water, they will drown and die. Leave for about eight hours. It will cause the clams to purge their innards of waste material. Then they are pure enough to include in any chowder. I like to leave them whole. Some like to chop them up.
If you really enjoy chowders head to your local library and find Jasper's cookbook on chowders. You won't be sorry.
And welcome to DC.