here's a rewrite w/WWW::Mechanize:

#!/usr/bin/perl

use strict;
use warnings;

use WWW::Mechanize;

my $url = 'http://www.datatool.co.uk/bikes1.asp';
my $url2 = 'http://www.datatool.co.uk/bikes2.asp';

open(DAT,'>',"c:\\cas.txt") || die("Cannot Open File");

my $mech = WWW::Mechanize->new();
$mech->get($url);
$mech->form(1);
my @manufacturers = grep $_, $mech->current_form->find_input( "Manufac
+turer" )->value_names;
foreach my $manufacturer ( @manufacturers ){
  $mech->get($url);
  $mech->submit_form(
        form_number => 1,
        fields => { Manufacturer => $manufacturer },
  );
  $mech->form(1);
  my @models = grep $_ !~ /Select Model/, $mech->current_form->find_in
+put( "Model" )->value_names;
  foreach my $model ( @models ){
     my $mech2 = $mech->clone;
     $mech2->submit_form(
        form_number => 1,
        fields => { Model => $model },
     );

    my $html = $mech2->content;
    ######################################################
    ######## This part is left as excerise to reader #####
    my $stream = HTML::TokeParser->new( \$html ) || die "Couldn't read
+ HTML string: $!";
    my $text = $stream->get_text('/table');
    print DAT $text;
    ######################################################
  }
}

close DAT;
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