I recently read IDEO’s HCD toolkit and it reminded me of the instruction offered in Ethnography for Marketers: A Guide to Consumer Immersion, which I have written about before. If you do any type of UX research, particularly observational research, but have not had formal research training I think you will find them both worthwhile reads. This is my summary of advice from both these texts on debriefing after a contextual inquiry.
I came across this video today made in 2008 by students from the IIT Institute of Design. It introduces design research and contextual inquiry and demonstrates what not to do when interviewing people. If your keen for tips on what makes or breaks a research session, its well worth watching.