Behold, the hundreds of free e-books about space history contained on this webpage.
From old favorites like The Difficult Road to Mars: A Brief History of Mars Exploration in the Soviet Union and Wind Tunnels of NASA to experimental work like Aerospace Food Technology and Life in the Universe: Proceedings of a conference held at NASA Ames Research Center Moffet Field, California, June 19-20, 1979, this is one of the best collections of space arcana you're likely to find.
These books were placed online over the last decade, so some of the formatting leaves something to be desired. Many of the works have been broken up into tiny pieces, forcing one to click through page after page. But this is a singular information repository, a storehouse for our fascination with flight.
What these works also show is how central the space program made and found itself during the 20th century. NASA could convene PIllsbury and the chefs on nuclear submarines to talk about food. Computing and solar energy were both pushed along by NASA's interest. The Space Race was a proxy skirmish in the Cold War. And, of course, all sorts of ideas from the era leaked into the way NASA thought about things: freedom and America and gender and aesthetics and the future.
Oh, and don't miss a personal favorite, We Freeze to Please: A History of NASA's Icing Research Tunnel and the Quest for Safety. A page turner.