Recently the analysis of social networks has proved successful for understanding many educational processes, and has led to dozens of papers on a variety of education-related topics and problems (Natriello, 2005; Watts, 2005), as well as to entire books explaining network research methods both to specialists and to wider audiences (e.g. Barbabasi, 2002; Buchanan, 2002; Watts, 2003). This paper proposes a way that the network perspective can illuminate difference in how textbooks are perceived and used, by analyzing book purchases related to purchases of textbooks. Using information available from the Amazon.com website as a starting point, the author suggests how patterns of correlated purchases (i.e. books also bought with a target book) suggest a strategy for understanding the character of particular texts about educational psychology, as well as the role of the text in teaching educational psychology. (Contains 1 table and 2 figures.)