use WWW::Mechanize;

my ($name, $city, $state);

my $url      = 'http://www.yellowpages.com/Index.aspx';
my $mech     = WWW::Mechanize->new(autocheck => 1);

$mech->get( $url );
$mech->form_name("__aspnetForm");
$mech->field("Mainhomectrl2:BasicForm1:businessname", $name);
$mech->field("Mainhomectrl2:BasicForm1:city", $city);
$mech->field("Mainhomectrl2:BasicForm1:state", $state);
$mech->click("Mainhomectrl2:BasicForm1:searchbtn");