My American Civil War Guerrilla Tactics from Osprey Publishing has been doing well. Amazon and B&N ratings are strong and I've found three reviews on the web. Civil War Book News gives a general summary without much of the reviewer's opinion, but any mention is always appreciated.
Two other reviews go more in depth. The History of War site is generally positive, saying I give a good general coverage, which is really all you can get from a 64 page book. The reviewer did quibble, "The title of this book is actually a little misleading. . .a more accurate title for this book would be Irregular Warfare of the American Civil War." This made me laugh, because that was the original title I suggested! Osprey's marketing folks thought "Guerrilla Tactics" would sell better, and they're probably right.
Civil War Books and Authors also reviewed my book, which made me happy because I've been a fan of this blog for some time now. They praised me for adopting historian Robert Mackey's three categories of irregular fighters: guerrillas, partisans, and raiders. Mackey's The Uncivil War was an important source for my own work and I recommend it highly. On the other hand, the reviewer criticizes my use of Brice's Crossroads as an example of irregular warfare. I included it because it was a good example of irregular warfare's use of terrain, superior reconnaissance, and aggressiveness to beat a supposedly superior force. Also, Forrest's tactics were a major inspiration for other cavalry raiders. But I see the reviewer's point--Brice's Crossroads is more battle than bushwhack.
The reviewer also says the book is too focused on Confederate fighters. I include many Union examples, but the bulk of the book and all the color plates are Confederate. This reflects the fact that the majority of irregular warfare was conducted by the Confederates owing to their need to compensate for their battlefield defeats and the large sections of secessionist territory held by the Union. While both sides conducted irregular warfare, the South needed it more.
In all, I'm happy with the reviews. They're generally positive and the few criticisms are put fairly and are more differences of opinion than true criticisms.