.: useful places
http://www.bbsdocumentary.com - Jason Scott's excellent and hugely comprehensive list of BBS software for all platforms.
http://www.textfiles.com - Another site by Jason Scott. All of the underground textfiles your heart could desire.
http://www.atariage.com - extremely knowledgable and active atari 8-bit (and more) community.
http://www.historyofphonephreaking.org/ - excellent site with historical info on phone phreaking