How to Ponass a Fish Over a Fire: Smoked Salmon: Bushcraft Tools Simple demonstration of very effective method of cooking fish.
Cactus Eating: Desert Survival Food and Water: Bob Hansler: In this video he demonstrates the harvesting, preparation and eating of a barrel cactus. He also discusses and shows a clip of removing spines with fire.
Coastal Foraging- Scallops, cockles, clam and crab; Beach cook up; The Fish Locker: I don't have experience with this, so I like this video because he shows you on the landscape exactly what you're looking for and about how to harvest them. I don't know how advisable the use of salt is to get the razor clams, but since it's a natural part of the ocean...? He ends with how to prepare and cook after gathering.
Stone Oven- How to Build/Use Primitive Cooking Technology: Horseback Bob This has step by step construction instructions for building a stone oven. It is well explained and illustrated and includes several videos including the building of the oven, baking bread in the oven and even how to use the oven as a smoker for cold smoking fish.
Extracting Salt from Plants: Practical Self Reliance: The article describes extracting salt from coltsfoot, but also includes other plants and in the discussion section, there is more information.
Link to Debbie Tremel's Pinterest account of images of Primitive Cooking