My first book was a history of the Soviet human space program entitled:

Challenge to Apollo: The Soviet Union and the Space Race, 1945-1974

It was published by the NASA History Division in 2000.

challengetoapollo

What's it about?

It's basically a narrative history of Soviet efforts to explore space. It was the first major work on the history of the Soviet space program based on the enormous amount of Russian-language information available after the collapse of the Soviet Union. So, it contains tons of stuff that was never previously published in the West. It's got a lot of technical stuff, but it's not an encyclopedia or anything. It's written like a story, so you can read it from beginning to end. It's got a plot. And it's not a short book. The main text is something like 800 pages long. Plus, there's tables and appendices that add up to about 1,000 pages.

It got a lot of awards and things like that.

•  The Wall Street Journal recently declared the book one of the "five best" books on space exploration [December 30, 2006]
The Eugene M. Emme Astronautical Literature Award from the American Astronautical Society (AAS) [2001]
Aviation Week and Space Technology year-end laurels [2001]
History Manuscript Award from the American Institute of Aeronautics and Astronautics (AIAA) [1998]

In the unlikely case that you might want to obtain a copy, you can get it from the following places (for about $80)

NASA Headquarters Information Center
U.S. Government Superintendent of Documents
NASA History Division

Yeah, I know it's ridiculously expensive. I had nothing to do with that.

The hardcover book was republished in a two-volume paperback version.
The text is exactly the same but the two volumes have different titles. They are:

siddiqi_sputnik siddiqi_soviet space race

They are both published by the University Press of Florida
They are available from their website: Vol. 1 and Vol. 2

Finally, here are some reviews of the book: (these are all pdf files)

Isis 96 no. 2 (2005): 308-309.
The Russian Review 63 (2004): 544-545.
Russian History/Histoire Russian 31 no. 3 (Fall 2004): 361-362.
Space Policy 18 (2002): 75-76.
Journal of the British Interplanetary Society 55 nos. 7-8 (2002): 240.
The Public Historian 24 (Winter 2002): 108-109.
Technology & Culture 42 no. 4 (2001): 817-818.
Quest: The History of Spaceflight Quarterly 9 no. 1 (September 2001): 62.
Journal of Military History 65 no. 3 (2001): 859-860.
Air Power History 48 no. 1 (Spring 2001): 69-70.
Spaceflight (2001): 175.
Astronomy 29 no. 3 (March 2001): 96-97.
Aviation Week and Space Technology, January 8, 2001.
Air & Space 15 no. 5 (December 2000/January 2001): 92.