Unfortunately the structure of the site makes offline browsing extremely difficult. If the table of contents were its own page rather than in a frame, I believe it would be easier. That is, if the site were "www.doom9.org/capture/" one could easily mirror it. Instead, the index is
http://www.doom9.org/index.html?/capture/start.html
When I try to save it as in offline bookmark in IE, it starts getting a ton of robot.txt files, and then gets stuck!
Oh well, really I'm just complimenting you on the great work--and I can always just save every page individually, not linked to each other.