Keep coming back with questions. This is why I voted for the iPhone-- practically anyone can tell you how to use it.
I say you ought to set up "find my iPhone" if you haven't already. It can play a loud beep if you misplace it or locate it on a map (and even lock it) if you lose it.
Also, rather than buying a book, I say google iPhone basics and you'll get a ton of helpful videos.
Kevin Slater