“The longest day” is a great book on the subject were they interviewed thousands of people who were personally involved in D-Day and wove their stories together as well
Not from D-Day or the European theater, but “With the Old Breed” is a really well done personal account of combat in the Pacific. It was part of the source material for Ken Burns’ “The War” and for the “The Pacific” miniseries on HBO.
Thanks, just bought it. "The Longest Day: June 6, 1944" by Cornelius Ryan (for others looking for it, there are multiple titles called "The Longest Day")