In reply to chris687:
This.
Asked the same question myself before and this was the most common recommendation. It manages to be fairly thorough but easy to read and digest, and is mainly practical info, with enough theory to back it up without straying into more academic territory.
If you read it, take everything in and can put it into practice then you'll be safer than most people on the hill. Thinking about it maybe I'm overdue a re-read...