This site is probably one of the best ways learn Perl that you can find. Come here often, read the questions, tinker with the problems and provide answers. Invariably you will find that one of your answers was wrong or incomplete and you will be (for the most part gently) corrected. Bingo, instant education. And it's free too (beyond the cost of the time you spend at it). Just imagine that, a free university which features lecturers that are among the best the field has to offer and nice people on the same level of knowledge as you * , that lets you set your own coursework and ask all the questions you want and never bugs you about doing your assignments by a specific date.
Will this prepare you for a test towards a certificate that says nearly nothing about your competence as a Perl programmer? Not very effectively. But it may help you to become competent enough that you don't need to take a job with people who rely on that kind of qualification.
Update: * Oh yeah, and there's a few people who won't answer the question you've asked and will insist on giving you their view on how best to learn Perl, e.g. me :-).
Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it. -- Brian W. Kernighan
