Here are a few books written by Jehovah's Witnesses:
"Jehovah's Witnesses, the New World Society" by Marley Cole; he also wrote "Triumphant Kingdom"
"Faith on the March" by A.H. MacMillan
"Jehovah's Witnesses: The African Connection: Unprecedented Preaching" by Firpo Carr; he also wrote some other books
"Facing the Lion: Memoirs of a Young Girl in Nazi Europe" by Simone Arnold Liebster
"Cotton: A lambs tail (Cotton for Jehovah's Witnesses children) Book 1 by Mary Rucker
"O'er the ramparts they watched" by Victor V. Blackwell
There are other books besides these.