I don't know if i'm understanding this... but at first look i must tell you that you have to generate 2 separate files: one with the html form (let's say 'form.html') and the other with the php code to send the email (let's say 'send.php').
Then you should do:
<form name="form1" method="post" action="send.php">
and in the file called 'send.php' you should put the code to send the email of course..
<?
$header = "From: ".$POST['$textfield3'];
mail($POST['select'],$POST['$textfield'],$POST['$textarea'],$header);
?>
As you can see, you will be getting the values from the form by post method.
And this would be enough to do what you want.
Good luck!
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