The Atlantic's Max Fisher has a roundup:
Flipping through a few of the many English-language tourist guides provides a fascinating, if non-scientific and narrow, window into how people from the outside world perceive America, Americans, and the surprises and pitfalls of spending time here.
Of the many pieces of advice proffered, four of the most common are: eat with your fingers (sometimes), arrive on time (always), don't drink and drive (they take it seriously here!), and be careful about talking politics (unless you've got some time to spare). But they say more than that.
In many ways, the tour books say as much about the world as they do about the U.S., by highlighting the ways in which American practices and standards deviate. Anyone who's traveled widely, particularly in the developing world, will understand why these books are so emphatic about, for example, punctuality, personal space, and the unreliability of our trains.
All of them, of course, have sections on tipping. It's difficult to overstate how confusing that can be to foreign visitors.