Recommended:
McQuarrie, E. F.
Customer Visits: Building a Better Market Focus. Newbury Park, Sage, 1993. [Very well written; the topic is somewhat specialized, but many of the points apply to qualitative research in general.]
If you want need a good marketing research reference text you might invest in Churchill's Marketing Research. It has everything (almost). Also, Churchill is the required textbook for 15.822.
Churchill, Gilbert A. Marketing Research, 6th Edition, Chicago: The Dryden Press, 1996. [Plus: Comprehensive and precise. Minus: Dry, expensive.]
Lehmann, Donald R. Market Research and Analysis. 3rd Edition, Homewood, IL: Irwin, 1989. [Plus: Well written, sensible. Minus: Virtually no coverage of qualitative methods.]
You will need a tape recoder for your interviews.
This material is tough to learn from a textbook. Therefore, a major element of the course is a survey-based group project. It breaks down into seven tasks, which roughly coordinated with the seven weeks of the course:
Selecting a topic and formulating a research plan
Preparing for customer interviews
Conducting and taping interviews
Transcribing the interviews and identify customer statements or "voices"
Interpreting or "scrubbing" the voices, and organizing into a hierarchy
Proposing a new concept or solution based on the voices
Writing the research report
A typical problem involves understanding the customers' perspective in a new market. You will have a lot of freedom in choosing the problem, as long as it allows application of all of the steps.