Preheat oven to 350°F. If the artichoke bottoms are canned, soak in cold water for one hour to remove the brine and vinegar taste. In a heavy-bottomed skillet, melt ¼ cup butter over medium-high heat. Add onions, celery, bell peppers and garlic. Sauté 3-5 minutes or until vegetables are wilted. Chop the cooked spinach very fine and add to the vegetables. Blend well and add lump crabmeat. Stir until all ingredients are well incorporated. Simmer 5 minutes then add ketchup, salt, pepper and hot sauce. Lower heat to simmer and cook 10-15 additional minutes. Add Herbsaint, blend into the crab and spinach mixture and remove from heat. Sprinkle in breadcrumbs and allow the mixture to cool slightly. Once cooled, stuff the center of each artichoke bottom with the crab and spinach mixture. Place the artichokes in a large baking pan and top with an equal portion of melted butter and sherry. Sprinkle with parsley and bake uncovered for 15-20 minutes. Serve 2 artichokes with a spoon of sherry-butter sauce. You may wish to place one whole oyster on the bottom of the artichoke prior to stuffing with the crab and spinach mixture