In a large, oven-proof dutch oven heat oil; add ham, chicken and sausage. Cook until lightly browned. Stir in onion, celery and green bell pepper and saute until tender crisp. Stir in seasonings. Add tomato sauce and chicken broth. Bring to a boil. Stir in rice and tomatoes. Cook in oven until rice is tender - approximately 20-25 minutes.