Bryce, I have studied this topic for a number of years, as my ancestor was in the Federal 8th Missouri Cavalry in 1864-65.
In researching his regiment I discovered Shelby's raid on the White River valley which them busy that summer of 1864. I have copied everything in the O.R. concerning this time period as well as a few non O.R. sources. It was an interesting little operation that kept the Union forces in the state confounded.
I've read the articles that Mark mentioned, they are good. For a long time most books or articles dealing with the war in Arkansas dealt with Pea Ridge, the Camden Expedition, and little else. I'm glad that more is being written about it. Contact me if you wish.