The purpose is to provide them with tools and resources that'll ease their first Perl adventures.

Well, first thing is knowledge, then the tools. Probably a demonstration of how to get things done with perl comes first, and I'd go with the advice of BrowserUk for that. But since they are programmers, I would - the knowledge part - talk about how perl is different:

• context, huffman coding, dwimmery
• data types (and references), namespaces, packages, scoping, bare metal OO system
• compile time vs. runtime, and switching back and forth
• BEGIN, CHECK, INIT ... END

and such. Perhaps firing up a gdb and examining the execution stack of the perl engine would give a good crack here. Oh wait, it is a talk, not a hands-on workshop... ;-)

I'd trade Data::Dumper for Data::Dump::Streamer, and show B::Deparse, Devel::Peek, Devel::Leak::Object etc., CPAN of course, and lastly redirect them here.