You can have a look at WWW::Mechanize and $mech->find_image() who returns a WWW::Mechanize::Image object

Update:

#!/usr/bin/perl 
use strict;
use warnings;
use WWW::Mechanize;
use Data::Dumper;

my $url = q{http://perlmonks.org/};
my $m = WWW::Mechanize->new();
$m->get($url);
print Dumper $_ for @{ $m->images };
[download]

Output:

$VAR1 = bless( {
                 'width' => '468',
                 'base' => bless( do{\(my $o = 'http://perlmonks.org/'
+)}, 'URI::http' ),
                 'alt' => 'Beefy Boxes and Bandwidth Generously Provid
+ed by pair Networks',
                 'name' => undef,
                 'url' => 'http://promote.pair.com/i/pair-banner-curre
+nt.gif',
                 'tag' => 'img',
                 'height' => '60'
               }, 'WWW::Mechanize::Image' );

$VAR1 = bless( {
                 'width' => '74',
                 'base' => bless( do{\(my $o = 'http://perlmonks.org/'
+)}, 'URI::http' ),
                 'alt' => 'Ovid',
                 'name' => undef,
                 'url' => 'http://perlmonks.org/images/usermonkpics/ov
+idmonk.gif',
                 'tag' => 'img',
                 'height' => '91'
               }, 'WWW::Mechanize::Image' );
[download]

hth,
PooLpi