What do I've to translate of my contact.php for spanish speaking people (www.eduardlid.net)? (I' ve tried to make a start!)

<?php
/* Set e-mail recipient */
$myemail = "eduard.lid@gmail.com";

/* Check all form inputs using check_input function */
$yourname = check_input($_POST['Su nombre y apellido'], "Ingresa su nombre y apellido por favor");
$email = check_input($_POST['email']);
$website = check_input($_POST['website']);
$comments = check_input($_POST['comments'], "Write your comments");

/* If e-mail is not valid show error message */
if (!preg_match("/([\w\-]+\@[\w\-]+\.[\w\-]+gresa)/", $email))
{
show_error("E-mail address not valid");
}

/* If URL is not valid set $website to empty */
if (!preg_match("/^(https?:\/\/+[\w\-]+\.[\w\-]+)/i", $website))
{
$website = '';
}

/* Let's prepare the message for the e-mail */
$message = "Hello!

Your contact form has been submitted by:

Name: $yourname
E-mail: $email
URL: $website

Like the website? $likeit
How did he/she find it? $how_find

Comments:
$comments

End of message
";

/* Send the message using mail() function */
mail($myemail, $subject, $message);

/* Redirect visitor to the thank you page */
header('Location: gracias.htm');
exit();

/* Functions we used */
function check_input($data, $problem='')
{
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
if ($problem && strlen($data) == 0)
{
show_error($problem);
}
return $data;
}

function show_error($myError)
{
?>
<html>
<body>

<b>Please correct the following error:</b><br />
<?php echo $myError; ?>

</body>
</html>
<?php