Hm afraid it's been so long since I've read any general books on it I can't really recommend anything.. but maybe a few quick questions might help others or remind me of something
How is your War of Independence knowledge? Would a book that covers both be better
Only national or also local? I quite enjoyed "Kilkenny in times of revolution" if you live nearby, although the Civil War section is small enough
Military/political, personal account/overview?