Dredge the shrimp pieces in flour. Heat oil in a medium-sized frying pan. Add the chopped garlic and sauté for 3-4 minutes. Add the shrimp and sauté lightly. Melt the butter in the pan and then add the white wine; stir to mix and bring to a simmer for 3 minutes. Add the beans, diced tomatoes, marinara sauce, basil, salt and pepper to taste. Heat over a medium flame for 6-7 minutes. Reduce heat and simmer for another 5 minutes. Serve over toasted slices of Italian bread.