All of the recipes in this book were created in Blender 2.56a, which at the time of writing was the latest official version available. Blender 2.56a can be freely downloaded from the Blender Foundation site in various computer system varieties. Currently it is available both in 32-bit and 64-bit versions for Linux, MAC, and Windows Operating Systems.
http://www.blender.org/development/release-logs/blender-256-beta/
Blender is being developed constantly but this version is feature complete and was used to produce all the recipes found in this book. As Blender moves towards its next milestone, Blender 2.6, its material and texture capabilities will improve but the settings described in the recipes should produce similar if not identical appearances to the images displayed.
Several recipes make use of images that are either created or modified in a paint package. You can use whatever paint package you are used to but if you haven't got one available I would suggest downloading GIMP, which is also free under a GNU General Public License.