The data and starting point for these examples are from Visualizing Data and Textbook Examples Visualizing Data by William S. Cleveland
ggplot2 examples are based on Graph Examples from Visualizing Data by William Cleveland
Visualizing.pdf contains the preface, TOC, and Chapter 1 from the book web site.
Elements.pdf contains the preface, TOC, and Chapter 1 of The Elements of Graphing Data from the book web site.