Here is a recipe found in the newspaper archives from 1918. Think WW1. It seems there was an acute white flour shortage at the time, so these recipes were suggested. Barley flour is not gluten free so be aware of that. These recipes do sound good and I will have to give them a try. How about you?
I wasn't even sure barley flour would be easy to find these days so I googled it, and there are suppliers, so you might be able to find it in your stores, or at least online if you are interested in trying it. I also found the following information about barley flour at this link: http://bakingbites.com/2008/01/what-is-barley-flour/