You can order a copy of the Font Flowers book online.
The Font Flowers are part of a larger goal of organizing fonts based on their formal properties automatically. With so many fonts available to a designer, organizing and searching trough them has become an impossible task. If there was a way to compare the formal properties of fonts and search through them easily, then studying and choosing fonts would be a much more educational and fruitful experience.
This project involved some FontLab python macros and Processing (ALPHA) with NanoXML and AWMartin's AIExport package. The FontLab macros were made to batch export XML files containing the outline data of the fonts (although I later found that Letterror's RoboFab does something similar). A Processing sketch batch processes the xml files to produce the flowers as illustrator files. NanoXML was used to parse the xml files, as explained by toxi here. AIExport was used to export illustrator files from Processing.