Order Modern Perl
Item Description: Take Control of Your Programming with Modern Perl
Review Synopsis: Great book for learning modern Perl best practices
The details of Modern Perl can be found in other reviews on PerlMonks. As it is freely available and anyone can look at the chapter descriptions, I won't review those here.
What I want to point out is the usefulness of this book for teaching best practices. The basic Perl part of the book isn't strictly necessary as this is covered in perlintro. However, many of the best practices cannot be found in perldoc or can't be found easily.
Such chapters as 2 and 7-12 are gold mines for best practices, many of which are difficult to find elsewhere unless searching specifically for them. Such things as the best community websites, Moose, style, exceptions, testing, warnings, reliability, security, idioms, things to avoid, and other tips are all considered in an uncluttered format, simple to understand and free to read ( although you want to donate on onyxneon.com.
Enjoy this modern, free, effective best practice guide.