Wing Chun Kung Fu: Chinese Art Of Self Defense
By James Lee
Its a very good book. Has not been watered down at all.
Has a brief intro and has a step by step analysis of the 108 moves of sil lium tao. It has some stuff on the different gates and some stuff on the trappings and chi sau.
If you just started this book is great and inarguably accurate.
Although, like you said, you cannot learn from a book, they can an impportant supplement to your training. Thinking and reading about something has alomst the same benefits as practicing it, as long as you are doing both!
Which school do you go to?
Good luck mate.