MetaCPAN.org is home to hundreds of thousands of Perl libraries. Perl has an amazing culture of documentation so be sure to look at the documentation there for any modules you use.
Guides for choosing the right library
There are so many modules on MetaCPAN it can be hard to choose the right one. Newer, better modules are released all the time making older versions obsolete. Luckily there exist a few guides to help you know which modules are the best for a given task.
The use of some libraries is discouraged.