This book should allow anyone with basic electronics skills to quickly design a passive Butterworth filter.
All possible low pass and high pass filters up to tenth order, and all possible band pass and band stop filters up to eighth order are covered.
Schematics and component values for these filters are given along with formulas for scaling the values to the particular frequency the filter must operate at.
There is a design example for each of the filter types that shows how to scale the component values. A Spice simulation file for the design is given along with the frequency response.
If you want band pass or band stop filters higher than eighth order the book explains how to use a low pass filter to construct them. So the information is there to construct filters up to twentieth order but we don't recommend trying to do that. The non ideal nature of the components makes it hard to get the expected extra performance.
The website for this book is http://www.abrazol.com/books/filter2/ where we will post related resources.