The complete Perl 5.8.8 documentation is available online at
http://perldoc.perl.org/, and on the main page you may download both the HTML (with a very useful included javascript search engine) and the PDF version. (
http://perldoc.perl.org/perldoc.tar.gz). I don't think other languages are doing any better in this regard.
update: BTW if you want to learn Perl, there are very good docs available here : http://www.techbooksforfree.com/perlpython.shtml
"Extreme Perl" and "Learning Perl the hard way" are especially worth reading.
update: I don't disagree anymore :)