1. The CSS Arkansas: A Confederate Ironclad on the Western Waters by Myron J. Smith, Jr. (McFarland, 2011).
Smith recounts in his typical level of detail the impressive highs and lows of the Arkansas's short career.
2. New Mexico and the Civil War by Walter E. Pittman (The History Press, 2011).
This work is primarily composed of a brief summary of Sibley's 1861-62 campaign, with an additional chapter covering the rest of the war years in the territory.
3. West Virginia and the Civil War: Mountaineers Are Always Free by Mark A. Snell (The History Press, 2011).
Snell's study is not a history of the war fought within the confines of the area that would become West Virginia in 1863 (though some of that certainly is in there), but rather a broader look at the contributions of West Virginia officers and men to the Union army's eastern theater campaigns and battles overall.
4. A Unionist in East Tennessee: Captain William K. Byrd and the Mysterious Raid of 1861 by Marvin Byrd (The History Press, 2011).
I can't say that I've ever heard of Byrd or his unauthorized 1861 raid, so the material presented in this one will be entirely new to me. Looks very interesting.