This is the first product that I have ever reviewed on Amazon, but I really wanted to take the time to do it as I have found this book and CD to be so invaluable. I am constantly picking it up for a quick reference, even after having owned a copy for years.
Obviously the way that actors learn accents varies from person to person, but for me this is just right. I love to know the "rules" of an accent, so study the phonetics of any accent very thoroughly - in this book there is a detailed description of the phonetic differences for each accent compared to standard RP (which is also explained in great detail at the start of the book). There really is a LOT of detail given, including explanations as to why any particular difference exists and pointing out any anomalies in the speaker's accent compared to others in that region.
Each accent has a word list and a transcribed passage recorded by a native speaker. However, just to make you aware, some of the recordings aren't of perfect studio quality (it sounds like some may have been recorded in the speakers' living rooms) but they are more than clear enough to hear accurately.
From what I can remember on the CD (I use the book for reference more than the CD nowadays), the word list and passage for each accent are spoken by opposite genders, again helping to pinpoint any differences there.
Yes, there are some major regional accents missing from the book, but they had to draw the line somewhere I guess. This book really is amazing value for money and I wouldn't be without it. Now if only I could find a similarly concise and detailed book for American accents!