Hard copies of the book are available to order from their site for $15, and Kindle copies can be purchased from Amazon for only $2.99. The authors also offer a free PDF download of the book from their website. That's truly in the spirit of building a better world.
Psychology for a Better World website: http://www.psych.auckland.ac.nz/uoa/home/about/our-staff/academic-staff/niki-harr%C3%A9/psychologyforabetterworld
Global Journal of Community Psychology Practice (GJCPP), free open access journal: http://www.gjcpp.org/
Post adapted from GJCPP book review by Judah Viola