Tonkin, Stephen: Binocular Astronomy, 2nd Edition
It would seem odd not to recommend my own book!
The first edition of this title was praised for its suggested objects for observation and especially for the finder charts for each object. In this second edition, this section is expanded in three ways. There are new objects, more information on each object, and a re-organization of the objects for binoculars for easier selection.
Binocular Astronomy 2nd Edition puts an emphasis on understanding binoculars and their use. The additional content reflects the latest developments in technology, new testing techniques, and practical ideas for binocular use. It also responds to the substantially positive reviews of the first edition, and is now even better suited to its target readership.
Cook, William J.: Binoculars: Fallacy & Fact
This is the book that other people wanted Bill Cook to write, before his insights and wisdom were lost forever.
Every chapter is written with the clarity, directness and economy that those who know him have come to expect from Bill Cook; it is born of a thorough familiarity with his subject. There is a vast amount of knowledge, wisdom and insight encapsulated in these pages and there is nothing that I did not find interesting. You will find stuff here that you just won’t find elsewhere. If you use, or intend to use, binoculars, you should read this book.
Ridpath, Ian and Tirion, Wil: Collins Gem: Stars
This little "gem" is often overlooked by serious astronomers, but its small format (8cm x 11.5cm) gives you a star atlas in your shirt pocket! Separate chart for each constellation, down to mag 5. Lots of DSOs, including the Messiers, are marked.
Consolmagno, Guy & Davis, Dan: Turn Left at Orion
The new edition of this excellent book, packed with viewing tips and clear instruction. Also realistic drawings of what you can expect to actually see.