That's a tall order and there aren't many books that would fit (and none perfectly that I know of). But here we go:
- Knuth: Digital Typography. Interesting set of papers by Don written about typesetting and his thoughts on it.
Papers and talks
Probably some papers in old tugboats available from tug.org, again it might be difficult to find them in the mass of technical papers.
There are several related papers in the DocEng conferences. But finding the right ones will probably be a challenge --- at least most of the older ones are available freely on the net e.g. epodd papers.
Some taped conference talks. You find links to them on the LaTex project web site, e.g. Here I mention two but perhaps there are a few others.
- Chris Rowley: A brief history of LaTeX — with a prediction: video via River Valley TV
- Frank Mittelbach: Windows of opportunity: A (biased) personal history
of two decades of LaTeX development — Are there lessons to be
Some papers of mine deal with some aspects of LaTeX history, see downloadable papers at Research Gate. e.g., LPPL history, Guidelines for future TeX extensions, The Pursuit of Quality and perhaps a few others.
There was a paper on Leslie's birthday on history of LaTeX by Chris Rowley "The LaTeX Legacy", which gives some interesting insights, but to my knowledge this is unfortunately only available at the ACM library.
Some partially related papers
Alexandre Gaudeul: The (La)TeX project: A case study of open source software (Barbara mentioned that already).
The TUG interviews. Some of them are surely giving a lot of insight into the history and evolution of TeX/LaTeX et al but it will be difficult to distill. By the way, most of them are available as a neat (non-free) book directly from the TUG website.
Rosemary Sasson: Computers and Typography only marginally related but contains a lot of the thoughts that have influenced Don and others at the time.