For any of you history buffs, check out the city guides from the Works Progress Administration--they're like the Yelp of the 1930s. The Los Angeles guide provides a beautiful snapshot of the city in 1939 and has been an essential research tool for my novels.
The WPA was created by FDR as part of the New Deal, and employed millions of out-of-work writers, artists, and musicians. Because of it, we have amazing art and well-documented history from the era between the Depression and WWII. The covers for my novels will emulate 1930s travel posters, the like of which were also funded by the WPA.
Re-prints of these books are readily available on Amazon.