I'm hardly qualified to reply after a pro like lhoward, but I think it depends on your existing programming abilities and what you want to accomplish using Perl. Only a year ago, I picked up Perl as my first programming since basic in college 15 years ago.

I needed to parse dial-up access router log files, so I bought "Mastering Regular Expressions", "Learning Perl", and the "Perl Cookbook" all from O'Reilly. Within a month I added "The Perl CD Bookshelf". With those titles under my belt, the included Perl docs and Web resources like Perl Monks make a lot more sense for other modest scripts I cobble.

If you already grok other programming languages (which I don't), I imagine there are better ways to get started in Perl. This is just what worked for me.

    cheers,
    ybiC