Another solution is MozRepl
Luckily, there is a Perl interface for MozRepl on CPAN.
I have also used Selenium and WWW::Selenium. They are really excellent products and indeed deserving of a much larger cookbook.
One project to watch is Bromine. It's a web front-end for driving Selenium test cases. Unfortunately, it only officially supports Java and PHP, but there are reports of people using it with Perl test cases. The project is in its infancy and could use some attention.