This book is exactly what it say it is, a qmail handbook.
Using this book, I was able to setup qmail and get it running without a hitch. I loved the layout of the book. Basically Sill gets right down to the task of why you bought the book- installing qmail. You can read "ahead" on the chapters and then walk through or you can simply walk through the book following the chapters and install qmail. The Appendices at the end where great. I personally suggest reading through these BEFORE you start the 1st chapter, but that is my own prefference.
The Appendices cover topics like "How qmail works", "qmail features", "Gotchas", etc. However, they are appendices so you can read them if you want to. Unlike the Sendmail bat book, where you have to wade through understanding internet mail and such, these are at the end in Sills book. It is a matter of prefference, but I would still recommend you read them (Especially the part on how qmail works!!!).
If you are new to qmail, and need to setup a server without straining you eyes on a computer screen, this is the book you need. It covers using qmail as your imap/pop server, as a external mail relay (a must for keeping your internal Exchange server secure), mailing lists, anti-spam, webmail, and many more features. This is really the only book you need if you are running qmail.