http://www.geocities.com/the-visitor/Buffybot/Buffybot.html
has articles on all of the robots in BtVS / Angel (plus at least one cyborg and someone who I suspect is neither a robot nor a cyborg, just very strange) and two seasons of Buffybot Adventures, one (complete) set between BtVS seasons 5 and 6, the other an AU set in BtVS season 6, so far running to five episodes. It looks like fun.
It'd still be nice to have a complete BtVS / Angel robot archive with stories from multiple authors, but this is an acceptable start.