Going Dutch in Beijing: How to Behave Properly When Far Away from Home by Mark McCrum is like a Miss Manners for travel. Chapters on greetings, gifts, food and eating, business etiquette and other topics share what to expect and how to act in different cultures.
What I like about the book is the way it not only tells you the customs, but in many cases, explains the reasoning behind them.
Why does that driver in Thailand tell you he knows where your hotel is, only to drive in circles all through town? It might be a bid to save face, not necessarily that he wants more money.
Why do some people only want to talk about personal subjects during a business meeting? If they are from certain countries, it could be because they won't do business with someone until they've gotten to know them on a personal level.
You will also learn when to show up for a dinner party and when you shouldn't finish all the food on your plate as well as how to act in several other situations. Many times, it is the opposite of what you expect. It can be startling to read what some cultures consider acceptable or offensive when it doesn't match your own beliefs.
This is a great book for learning about the different cultures you might experience when you travel. Keep in mind, variations of these customs might be practiced in different parts of the countries mentioned, but at least they'll be somewhat familiar to you.