The Sicilian Dragon is still a good defense for black! The main lines lead to tremendously complex positions in which both sides attack freely. One slip could be fatal, and a deep knowledge and understanding of the opening is often a decisive advantage.
In this book IM David Vigorito focuses on all the critical Yugoslav Attack lines, examining the most important and instructive games in recent years (up to 2012) and highlighting the main developments and novelties for both sides.
Like all opening books, the material is dated as soon as the book is published, but the author provides a good survey of BASIC theory in this defense which is still a viable option as black. The book is not a comprehensive Dragon repertoire book. It covers 9. Bc4 and 9. 0-0-0 and g4 very thoroughly, so you will need additional resources if white plays anything other than the Yugoslav Attack.
The good point is that it is organized with the major variations in bold type and the author provides ample descriptions of why certain moves work out well or poorly, which makes it easy to study.