I liked Perl by Example by Ellie Quigley. It's on its third edition, but personally, I enjoyed the first edition. It was far more compact. But the beauty of Perl by Example is that it shows you:

1) The source code of a program line by line - with explanation.

2) The output of the program after its been executed, line by line - with explanation.

You could actually read this book and learn without even being near an editor, Perl interpreter, or a computer for that matter. I have given away several copies of the first edition, and picked up the latest edition as a helper/reference for the office.