Start with high-confidence guerrilla warfare books, then narrow by subgenre or adjacent topics.
Once an Eagle
Anton Myrer, Carlo D'Este
82 Days on Okinawa
Robert L. Wise, Art Shaw
The Generals
Thomas E. Ricks
The Forever War
Dexter Filkins
To Lose a War
Jon Lee Anderson
The First Total War
David A. Bell
The Long War
David Loyn
Waging a Good War
Thomas E Ricks