4 links
Classic Computing Mailing List
classiccmp.org
Mailing list of nearly 1000 members dedicated to preserve and archive classic computer documentation and software.
Doug Jones's DEC PDP-8 Index
cs.uiowa.edu
All about the PDP-8 computer; emulators, documentation and history.
Highgate's PDP-8 Page
highgate.comm.sfu.ca
Documents for PDP-8 minicomputer, covering hardware, software, and supporting materials.