Courtesy of the Library of Congress: a treasure trove of color photographs from the 1930s and 1940s, in an the exhibit America from the Great Depression to World War II, conveniently indexed by subject, geography and creator. There’s all sorts of interesting things to dig up – this shot looks like a still from an old movie.
You can also search through the much larger collection of black & white photographs. I found this group of pictures from Q-town.