Cook sausage in a large skillet over medium heat, stirring until it crumbles and is no longer pink. Remove sausage, reserving 1 tablespoon drippings in skillet. Drain sausage on paper towels.
Sauté onion and celery in hot drippings over medium-high heat until tender. Remove vegetables with a slotted spoon.
Combine sausage, vegetables, cornbread, and remaining ingredients in a large bowl, stirring gently until moistened. Spoon into a lightly greased 13- x 9-inch baking dish.
Bake, covered, at 350° for 30 minutes or until thoroughly heated.