This was by far the best book I read prior to my trip to China. This book goes into detail about things that are actually important when you travel in a culture that you are unfamiliar with. This book touches even on subjects that are sensitive.
Written in 1990, it's a bit dated (Hong Kong was handed back to China in 1997, that's important). I didn't go to China, but this book was very helpful to understand the Chinese immigrants coming to the US: why they do things the way they do. This book is worth a look.