Winterizing

As we head for winter here in New Hampshire, we're concerned about the winterizing process. The description in the manual seems too easy. We live where you can expect hard freezes by early November and are worried about making sure there is no water in the lines, pump, or water heater. Do we need a bypass? How do we assure that the water heater is empty? How much anti-freeze will we need? Are there other questions I haven't asked that I should be thinking about? - Ted