If you don't find an entry in the standard library that fits your needs, it's still quite possible that someone has written code that will be useful to you. There are many superb library modules that are not included in the standard distribution, for various practical, political, and pathetic reasons. To find out what is available, you can look at the Comprehensive Perl Archive Network (CPAN). See the discussion of CPAN in the Preface.
Here are the major categories of modules available from CPAN:
Perl core modules, Perl language extensions and documentation tools
Networking, device control (modems), and interprocess communication
Filenames, filesystems, and file locking (see also filehandles)
String processing, language text processing, parsing, and searching
Option, argument, parameter, and configuration file processing
Images, pixmap and bitmap manipulation, drawing, and graphing
Filehandle, directory handle, and input/output stream utilities