Zen Cart is a world class fully blown e-commerce engine to make you e-store. Unlike it rivals, you can sell both physical goods and electronics goods (like ebook, softwares) using this (without adding mods).
To learn such a extensive software quickly, its always good idea to read structured manuals. Unstructured manuals may serve the same purpose, but will kill more time and you will miss the sequences of discussions.
In the book, the author made every efforts to explain each and every settings, configuration etc. of the Zen Cart shopping engine. So, if you are completely new to e-commerce, I believe you will not be bored. Experts users may easily ignore certain things known to them as the author wrote section by section in different paragraph.
I found Chapter 1 very interesting. The authored discussed many things of Zen Cart and its rivals. Even, there was a very good discussion on Zen Cart’s parent, and also rival, osCommerce. Morever, you will get gross ideas on different e-commerce engines like Virtual Mart (Extension of Joomla), x-Cart, AgoraCart. Author’s logics behind using Zen Cart over osCommerce must convince you unless you expect an less/non-extensible web shop.
In the second chapter, the authored discussed the installation in many ways. Part of 2nd chapter and the 3rd Chapter are the most important to kick start your web shop where details configurations of Zen Cart were discussed. Using necessary photos will make things easier to understand.
The remaining chapters are the second phase of your web shop. You will learn how to customize the templates, translating it, Promoting your shop, Maintenance and Troubleshooting. The customization chapter is quite elaborative.
Chapter 7 is for existing osCommerce users willing to migrate to Zen Cart while Chapter 8 are for those who wants to link Zen Cart with existing sites/CMSes.
The only thing you may miss is the tutorial of module/extension development. But I believe that is the scope of a separate text, which might have forced the author to exclude it.