I, too, write WW2 novels and I become absorbed in the era by listening to the music, reading magazines from the time, and watching movies done in the 1940s.
I was really daunted by my last novel (currently halfway completed) because it was set in D.C. during WW2. I just didn't think I could get all the details right with the resources I had (though they were really, really good)- so I put it aside for awhile, to be picked up again sometime in the future (and besides, the plot needs a major revamp).
I'm currently writing a WW2 novel set in Nebraska, my home state, and that has proved a blessing in disguise. I'm in love with the story and also don't have to do near the research because I've lived in Nebraska my entire life. Plus, the historical archives are right where I live, and we have an amazing exhibit at the state museum just on our state's involvement in World War II.
It's rather interesting, really, considering I used to find Nebraska boring as hell as a youngster. But the more I unearth, the more I realize it's not boring at all, and with the research right at my fingertips, I'm having an amazing, grand ol' time!