Dr. Nikos A. Salingaros, http://sphere.math.utsa.edu/sphere/salingar/, is a professor of Mathematics at the University of Texas at San Antonio.
He has collected Some Notes on ChristopherAlexander at http://sphere.math.utsa.edu/sphere/salingar/Chris.text.html, and the forthcoming series the NatureOfOrder by ChristopherAlexander at http://sphere.math.utsa.edu/sphere/salingar/NatureofOrder.html.
I highly recommend his (co-authored) paper on cities as information processing systems: http://applied.math.utsa.edu/~salingar/InfoCities.html.
He also wrote "Anti-Architecture and Deconstruction" (ISBN: 3-937954-01-5 ; UMBAU-VERLAG, 2004).
Fascinating discussion of information processing role of cities, which draws on both ChristopherAlexander and HerbertSimon's organization theory.