Books for sailing rules don't seem like a whole heap of fun, but they're not as dry as you might think - they've certainly improved a lot over recent years.
They're also pretty important. If you do a fair bit of racing then it is very useful to own a copy of the racing rules, but also to have one or two book that explain the rules as they occur on the water. This added context can get you out of a lot of trouble sometimes, and they can also help resolve a rules issue without ending up in the protest room. And, if you do end up in the protest room, then they'll guide you through the process and hopefully help you get the result you want.
This book is widely recommended - it has great descriptions of the rules as the actually occur on the water, along with very clear illustrations to demonstrate each point. It also includes the actual Racing Rules of Sailing in the back, so you get the complete rules too.
I have written a full review here.
Various editions of this book have helped sailors all around the world understand the rules of sailing for over 45 years, and it is easy to understand why. If you're going to look for help understanding the rules then you can do far worse than to listen to arguably the greatest dinghy sailor of all time.
Comprehensive, with clear illustrations, and with a complete copy of the Rules at the back of the book, this is an excellent and hugely popular guide to the current rules of sailing.
A very popular and clear book covering the Racing Rules of Sailing.
UK & Ireland
As books for sailing rules go, this one has to be one of the most useful. We often learn best when we have to figure things out, and quizzes are one of the best ways to think things through and also to test knowledge.
This book also happens to have one of the best covers for a sailing rules book, which is an added bonus...
The Racing Rules of Sailing including US Sailing Prescriptions. Also includes the Race Signal Flags and International Code, and the US Sailing Protest Form.
There is a normal paperback edition available of this too.
The RYA also have a Handy Guide to the Racing Rules 2017-2020 available.
UK & Ireland
Sometimes you've just gotta laugh. The rules can be confusing, complicated, frustrating or boring. Sometimes they are all four of these things. when they are, it's no harm to have something like "The Unofficial Rules of Sailing" to hand to cheer you up again.
A perfect present for the rules buff (or rules breaker) in your life.