I don't know that I would consider Hidden Power to be an introductory book. Certainly it was created with a more advanced user in mind. It does not go through use of most basic tools (though there are instructions on using clone, healing, levels, curves, and many of the tools I consider --and outline as--the basic tool set). I feel that most basic instruction and orientation can be had by reading the user manual...ahem...and just playing with the tools.
That said, I have received quite a few emails from people who are both good with computers and with photography who have said it was a good introductory book. Please note, good with both...by that I mean someone at least competent in installing and uninstalling programs, with 3 or more years of computer experience, and serious amatuer status as a photographer. A competent photographer who is frustrated with computers may have too much of the technological leap, and a competent computer user with little photographic background may care less for the approach, that tends closer to a photographic perspective.
You'll be able to follow the step-by-steps at whatever level--you just might find it hard to understand what is going on.
Did that help?
PS - i DON'T recommend starter books if you are serious about image editing because you will quickly outgrow them, and you'll have wasted the investment. In my mind you will do better with a few targeted web tutorials and the manual than with a book that re-hashes the manual--albeit in a friendlier way. My book is made to be one you won't soon outgrow...and I'll admit it isn't light reading. It compresses most of my Special Edition Using book from 900 to 300 pages, and adds some theory.