It would be good to see your sendto.php code but I will take a shot anyway.
Below is an example from the php.net manual. I added the $guest variable. note the use of variables in the mail() function. Using the variable for message body to simply build a string that includes your form variables and body text together. Note how I used the $guest in the body:
EXAMPLE
<?php
/ test variables /
$guest = "Susan";
/ recipients /
$to = "mary@example.com" . ", " ; // note the comma
$to .= "kelly@example.com";
/ subject /
$subject = "Birthday Reminders for August";
/ message /
$message = '
<html>
<head>
<title>php mail test</title>
</head>
<body>
<p>Hope this sends mail!</p>
<table>
<tr>
<th>Crazy Person</th><th>Day</th><th>Month</th><th>Year</th>
</tr>
<tr>
<td>'.$guest.'</td><td>3rd</td><td>August</td><td>1970</td>
</tr>
<tr>
<td>Sally</td><td>17th</td><td>August</td><td>1973</td>
</tr>
</table>
</body>
</html>
';
/ To send HTML mail, you can set the Content-type header. /
$headers = "MIME-Version: 1.0\r\n";
$headers .= "Content-type: text/html; charset=iso-8859-1\r\n";
/ additional headers /
$headers .= "To: Mary <mary@example.com>, Kelly <kelly@example.com>\r\n";
$headers .= "From: Birthday Reminder <birthday@example.com>\r\n";
$headers .= "Cc: birthdayarchive@example.com\r\n";
$headers .= "Bcc: birthdaycheck@example.com\r\n";
/ and now mail it /
mail($to, $subject, $message, $headers);
?>
razz