Just a wild suggestion:

• Download a first page.
• Download a second page.
• Do a diff between the two pages and you have the content that has changed.

A module such as Algorithm::Diff could be useful here.

PS: if this algorithm works, you may use it for free, just call it "CountZero's Universal Scraper Algorithm"!

Update: Could be as easy as this:

use strict;
use warnings;
use 5.012;

use LWP::Simple;
use Text::Diff;

my $first_content  = get('http://www.thinkgeek.com/geektoys/all/');
my $second_content = get ('http://www.thinkgeek.com/geektoys/feature/d
+esc/1/60');

my $diff = diff \$first_content,   \$second_content;

say $diff;
[download]

of course you will have to parse the diff-output!