The original culture of the pre-populist Internet and the deeply-held beliefs of Perl's author, Larry Wall, gave rise to the free and open distribution policy of perl. Perl is supported by its users. The core, the standard Perl library, the optional modules, and the documentation you're reading now were all written by volunteers. See the personal note at the end of the README file in the perl source distribution for more details. See perlhist (new as of 5.005) for Perl's milestone releases.
In particular, the core development team (known as the Perl Porters) are a rag-tag band of highly altruistic individuals committed to producing better software for free than you could hope to purchase for money. You may snoop on pending developments via the archives at http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/ and http://archive.develooper.com/perl5-porters@perl.org/ or the news gateway nntp://nntp.perl.org/perl.perl5.porters or its web interface at http://nntp.perl.org/group/perl.perl5.porters , or read the faq at http://perlhacker.org/p5p-faq , or you can subscribe to the mailing list by sending perl5-porters-request@perl.org a subscription request (an empty message with no subject is fine).
While the GNU project includes Perl in its distributions, there's no such thing as "GNU Perl". Perl is not produced nor maintained by the Free Software Foundation. Perl's licensing terms are also more open than GNU software's tend to be.
You can get commercial support of Perl if you wish, although for most users the informal support will more than suffice. See the answer to "Where can I buy a commercial version of perl?" for more information.