echo "Data has been submitted to $to!"; 
mail($to, $subject, $body); 
} else { 
echo "blarg!"; 
}

// if the mail was sent successfully
if(mail($to, $subject, $body))
{ 
    // redirect the user to another page
    header('Location: http://www.example.com/'); exit;
}
else
{
    // otherwise, tell them something went wrong
    echo 'Oops!';
}