"The Brass Tacks of Market Research" (pdf) -- how to conduct market research to assess the market for your idea -- Suzanne Miglucci, VP of Marketing and Strategic Alliances at SciQuest -- Nov 2006
The best place to start is by attending a Duke Entrepreneurship Education Series (DEES) event or by watching one of the numerous prior speakers. Streaming video of the talks and slides are available for all events, including Entrepreneurship 101, Financing 101, Venture Capital 101, Business Plans 101, and Elevator Pitches 101 among others.