Yes, countZero makes a great point. Lower level languages do enhance your knowledge for sure, however the entire time you may be thinking " wow I could do this whole page in one line of perl " lol. Don't just use perl for work use it to make something interesting and that you have a connection with. This can make it a lot more fun and valuable in the future!
I began my journey with Programming Perl 3rd edition. The 4th ed. just came out about a year ago so you want that one, many great revisions and additions. I too have the cookbook but regretably to be honest I rarely ever used it since google can provide me with a solution way faster. Otherwise it has some solid examples.