Quaker Oats had a booklet many years ago...
I no longer have the booklet, but they sugest grinding oatmeal in a food processor and subbing 1/2 the white flour with the ground oats at the rate of 11/4 cup ground oats for 1 cup all purpose flour.
I have done this for years with great success. Most muffin, quickbread, and scone recipies work just fine. You can try upping the ratio of oats to white flour , and over time most people will not even notice.