The following is a list of books that I recommend for any person interested in reading more about the two world wars. It's by no means exhaustive, and there are many other great reads out there, but these are the ones that I personally recommend:
1- All Quiet on the Western Front by Erich Maria Remarque. The quintessential trench warfare novel, the graphic details within this book can be frightening to many readers, as it should be.
2- A Farewell to Arms by Ernest Hemingway. A solid read from one of literature's manliest of writers, the distinctly macho flavour of this book is softened by its stark attention to detail and total lack of sentimentality; appropriate for this genre.
3- Mr. Britling sees it through by H.G. Wells. While Wells is more commonly known for his science fiction works such as the Invisible Man or the Island of Dr. Moreau, Wells never considered himself to be a science fiction writer and wrote many quality pieces of literature regardless of genre or type. This novel is heart-wrenching, as seen from the point of view of one man who doesn't actually fight in the war, but does suffer.
4- Bonheur d'occasion by Gabrielle Roy. Known as the Tin Flute in English, this book takes place in the quartier St. Henri in Montreal during the first world war and is centered around a poor working class French family. It offers a unique perspective of the war from afar, where recruitment came down to a question of righteousness for upper class Canadians or a winter jacket and three square meals a day for the working poor. The book loses some of its character in its English form; highly recommended in French for those who can.
5- The Diary of Anne Frank. The thing that struck me the most about this tragic tale is the fact that the point of view is so fresh, frank and girlish. Anne Frank is very much a child, and her writings reflect the preoccupations of her age as well as a developing sense of self in the most extraordinary of circumstances. A truly inspirational and very human read.