Same thing bugged the hell out of me. Here's how I do it. This program takes input from a generated form and prints it to the browser.

Make sure you have CGI.pm installed

#!usr/bin/perl -w  #include warning switch

#loads CGI with standard shortcuts
use CGI qw/:standard/;

#good for keeping track of variable scope, etc
use strict;

my $name = param('name') || '';

if($name) {
   &page2;
} else {
   &page1;
}

sub page1 {
print header;
print '<form  method="post" action="thisfile.pl">';
print '<input type="text"   name="name">';
print '<input type="submit" value="submit">';
print '</form>';
}

sub page2 {
print header;
print 'Hi, '.$name.', your variable has been submitted.';
}
[download]