If you are looking for a good reference book to construct a "professional" studio then Phil Newell's (author) book is for you. The investment in this book will be for life, and not something you read then give away. I showed the book to an architect friend, and he came up with the "good stuff" moniker in the title of myreview, and promptly purchased the book for his office.
The book is HIGHLY technical, and Phil goes to the trouble of explaining why things are constructed in the manor he describes. There is a lot of math, science of acoustics, and the physics of sound transfer. So it might be over the head for most people. It's not something the average band member looking for a crib to record his tunes is going to find of use.
If you are a serious musician, and have an architect and contractor build the studio for you, INSIST they read this book! The advice Mr. Newell gives will keep you from having that 'aw darn' moment in recording when something doesn't sound right. If you have the aptitude for high-end commercial construction techniques, or have worked in the professional construction trades you will get 95% of what Phil talks about. The other 5% is the math and acoustic reflection properties which can seem like voodoo.
The book covers all the basics from walls, to floor, windows, reflective surfaces, etc. Sections explain control room design, speaker placement, and acoustics to get the best representation of the recorded sound.
If you're a small time musician or gearhead that wants to build a studio in your home, garage, or small building, there are plenty of other good "cheap" books out there to get you started. I would not start with this book as it might frustrate you. But if you are serious, and I mean really serious about doing it right, and having a sound stage that people will talk about, then this book is worth the price.