I have never heard of local::lib or @INC until this thread.

@INC is mentioned in the FAQ, perlrun, the documentation for lib and, of course perlvar. I'm slightly surprised that you've read none of these yet.

It shouldn't be so difficult to do something so simple.

Where's the difficulty? Just set up your environment properly as outlined in Re: Perl app won't compile /run from cron and you're there.