I bought this book when I was about to produce my first show. I got a few books about theatre how-to's and have always found the Crowood Press Practical Guides very useful.
This book is easy too read, offers enough detail without being too detailed and is most certainly written with practicality in mind. It most certainly gave me the tools (and by doing so the confidence) of producing my first show successfuly!!
Although the principles of Production Management do not change much over time, this book feels a little bit outdated. The content is very much appicable to now, but the lay-out of this book feels like it hasn't changed much since the 80's - that shouldn't hold you back though!
Also something to keep in mind when buying books about theatre subjects is that language and practices can differ slightly between the US and the UK - make sure you buy a book aimed at the right country!