Buttermilk
Stir one tablespoon of lemon juice into one cup of lactose free milk and leave at room temperature for 10 minutes. Once the milk thickens, use it in place of one cup of buttermilk.
This substitution is used in Buttermilk Crumb Muffins, Scones, Buttermilk Pound Cake and more.
Cake flour
Whisk two tablespoons of cornstarch into one cup minus two tablespoons of all purpose flour. Use this as a substitute for one cup of cake flour.
This epicurious article also has a substitute for self rising flour.