I recently had to use Excel in a way that I had never done before. Sometimes the "help" feature on Excel doesn't seem to help very much, so I decided to borrow this book from the library so I could look up my questions as I did the new tasks.
What I discovered first was that the index isn't very complete. Some of the answers I needed could be found by using the index, but most of them required me to read the book from front to back. When I checked to see if the sections I needed were in the index, I found they were not.
The second problem I had was that the terms used in the text were hard to track down, so even if a section was easy to find from the index some of the information was unintelligible to me.
So I went back and read the whole book, and followed it quite easily.
I didn't like the examples too much. They were pretty juvenile.
I then compared this book to the Excel Bible which I had used recently for a similar purpose. I found the Excel Bible was much easier to use for reference, contained a lot more information, spelled out more ways to get the same tasks done and wasn't sound bound up in terminology.
If you want to get past doing only very simple tasks on Excel, you should plan to graduate to the Excel Bible. If you are confidence that you can read and understand new subjects, you can probably start with that book.