Book: Radical Landscapes
Radical Landscapes: Reinventing Outdoor Space is something akin to the glossy, high-fashion magazines and fashion shows, only directed at gardening. While the average gardener probably wouldn't want to implement these radical garden designs. they are great ways to spur your thinking and help you develop new ideas for your garden.
Additionally, public designers will find some great ideas that have already been implemented, along with some information on how the design works with public usage. The photography is excellent and many of the designs include drawings and in-depth discussions of the concepts and thinking behind each design.