Perl's Official Documentation
The first place to check is always the manual.
All the Perl that's Practical to Extract and Report - A great resource for Perl news.
The Perl Mailing List Database
A resource full of Perl mailing lists. This has some nice general ones for new users and plenty of specific, focus lists.
The official Python documentation is very comprehensive, and includes several nice tutorials.
A collection of Ruby documents and documentation.