I have this book in my library, and was glad to have been able to buy it before it became near impossible to find. But now it’s available for free online. It’s not an especially good book, but it has great art, in the Golden Guide tradition, and is quickly read and enjoyable. If you like this kind of thing you will like this.

http://www.scribd.com/doc/77046680/Hallucinogenic-Plants-A-Golden-Guide

The Golden Guide to Hallucinogenic Plants