Second Order Cybernetics

Chilean School of Biology of Cognition
Offering overview of Maturana's contributions to psychology, 'Ask Professor Maturana', and online archive editions of important articles.
http://www.inteco.cl/biology/index.htm

Radical Constructivism
The most comprehensive Webspace on constructivist epistemology (a component of the second-order cybernetics worldview), especially the work of von Glasersfeld and von Foerster
http://www.univie.ac.at/constructivism/

Towards an Ecology of Mind
Well-organized site addressing (e.g.) Gregory Bateson, Humberto Maturana, Ernst von Glasersfeld, Heinz von Foerster, and George Kelly.
http://www.oikos.org/psicen.htm