Season Ribs With Salt And Pepper To Taste. In A Large Skillet, Over Medium-High Heat, Brown Ribs On All Sides. Place Half Of The Onion, Green Pepper, And Celery In The Bottom Of A Slow Cooker. Place Half Of The Ribs On Top The Vegetables, Then Repeat Layering With The Remaining Vegetables And Ribs. In A Medium Bowl, Stir Together The Tomato Sauce, Brown Sugar, Vinegar, Lemon Juice, And Worcestershire Sauce. Pour Mixture Over The Top Of The Ribs. Cover, And Cook On High For 1 Hour. Reduce To Low, And Cook For Another 8 To 9 Hours.