There are a ton of WWII novels set in the 40s. You may like The Winds of War and War and Remembrance by Herman Wouk which are more than battlefield stories.
On the home front there's Red Sky At Morning by Richard Bradford(excellent), On the Road by Jack Kerouac, Catcher In The Rye by J.D. Salinger, Nemesis by Philip Roth, and The Golden Age by Gore Vidal. The Cryptonomicon by Neal Stephenson has scenes set in the 40s.
For the 50s, there's Wicked City by Ace Atkins, LA Confidential by James Ellroy,