Programming Perl (second edition) http://www.ora.com/catalog/pperl2/
The "camel book" is the definitive Perl reference book by none other
than Larry Wall, the author of the Perl programming language
Mastering Regular Expressions http://www.ora.com/catalog/regex/
The "hip owls book" is a general text on regular expressions (check out
the author Jeffrey Friedl's
Perl Page
as well) with a bias towards Perl, arguably the best pattern matching
language in existence today
The Perl Journal http://tpj.com/
A Perl technical journal published quarterly
Miscellaneous
The Perl Language Home Page http://www.perl.com/perl/
Software, training, resources, a search engine, and the mammoth
Perl FAQ
Matt's Script Archive http://worldwidemart.com/scripts/
Links to many useful and freely-downloadable CGI scripts, primarily
Perl scripts but others as well (most notably C++)
