In a large frying pan, heat the oil over medium high heat. Add the zucchini, eggplant, onion, bell pepper and mushrooms. Sauté for 10 minutes or until crisp tender. Add the shrimp and cook for 2 minutes stirring frequently. Add tomatoes, garlic salt, basil, parsley, and black pepper. Cover and simmer about 5 minutes or until shrimp are just tender being careful not to overcook. Serve over a bed of couscous or rice.