There is a wide array of resource material for Perl and for bioinformatics programming. This list is not at all exhaustive, but it includes those resources, both online and in print, that I think you may find interesting and useful as you expand your Perl programming repertoire.
The documentation for Perl is extensive. It includes lists of FAQs (Frequently Asked Questions, with answers), tutorials, precise definitions in the form of Unix-style manpages, and discussions of specific areas. There are various web sites, a well-organized storehouse of useful Perl programs called CPAN, newsgroups that have searchable archives, conferences, and many good books. It's also worth your while to find and cultivate your own local Perl community. Don't be afraid to engage your colleagues, though as your programming skills grow, they're liable to start asking you questions!
As I've mentioned before, Perl is free. It's part of the wider open source movement, which includes such developments as Linux, the Apache web server, and so on. Since Perl is free, it relies on a community of interested parties to develop code and to write documentation. Because of this, you may notice that a lot of the documentation is a bit fragmented (or, in some cases, very fragmented). Still, the level of support for all these projects equals that available for the best of the commercial software packages.
This is the starting point for all things Perl. By all means, ...