Mac users should make sure to visit, bookmark, and subscribe to the RSS feed for Maria’s Guides:
Maria’s Guides — Support and additional material for readers of books and articles by Maria Langer.
Maria and I collaborated a couple of years ago on the book WordPress 2 Visual Quickstart Guide. That was my first real published book, but it was Maria’s 60th or so book. Her titles include MS Word and Excel, The Macintosh operating system, Quicken, and others.
At Maria’s Guides you’ll find all sorts of useful information about using your Mac.