Why this book?
There are plenty of resources that teach you which formulas to use, how to use them, when to use “$” in your formulas etc but there very few resourses, almost none on how to organize your sheets, organize your data in a way that makes data more understandable and your sheets easier to use.
I am sure you have encounter many cases where superior, client or your personal curiosity let you a question that should be easily anwered by looking at your sheets. For example, lets imagine you work in a book shop and you want to find out what gene has been the top seller over the past year, well you have the sales data, you should be to count sales by genres and find out which one sold most and viola, you got your answer... only to find out that you have one sheet per month, so your analysis needs to be repeated 12 times (once per each month), and also the genere is sometimes included by some publishers but not others, some publishes include the genere but embeded withi other information about the book like its publing date or the number of pages.