Some books i have read about WWII that aren't written by survivors (they are fiction, I don't know if that is what you want though) Are:
Number the Stars by Lois Lowry
Surviving Hitler by Andrea Warren
Mother of the Holocaust Children (I forgot author, but the Hallmark Hall of Fame movie, The Courageous Heart of Irena Sendler, is based off this book)
Shelter Me by Alex McCaulay
Sarah's key by Tatiana De Rosnay
If you were looking for non-fiction books, well, I haven't read any but Sarah's Key has true facts about Jews In Paris France, and Surviving Hitler has lots of true facts about Concentration Camps.
