1. Guerrilla Warfare in Civil War Kentucky by Gerald W. Fischer (Acclaim Pr, 2014).
Like many guerrilla studies, this one appears to be primarily personality focused, with chapters covering individuals and bands that operated in Kentucky (ex. those of Mundy, Johnson, Quantrill, Magruder, and many more lesser known figures). The source array is limited to newspapers, books and articles. Though they're fairly common for Missouri, I don't recall a recent synthesis of this type for Bluegrass State bushwhackers and partisan rangers.
2. The March to the River: From the Battle of Pea Ridge to Helena, Spring 1862 by Robert G. Schultz (Camp Pope Publishing, 2014).
Samuel Curtis's post-Pea Ridge change of base from NW to NE Arkansas has been covered in bits and pieces in the literature, as has his capture of Helena when Little Rock could not be reached, but Schultz's book is the first full treatment of the entire operation. I like what I see so far.