Having started to learn elvish and some of tolkiens other languages, I bought this book. At first I thought it was fantastic, but now that I've read more into it, there are a lot of inaccuracies, and I don't feel the author has used the texts written by Tolkien to their full potential. If you are looking to learn elvish/Tolkiens languages, try Jim allen's introduction to elvish. Its a little heavy going but very comprehensive.
In short,if you are really looking to learn about tolkiens languages, don't waste your money on this book- there are better resources out there!