Not sure what's in those files, but you can do something like this:
$message = $_POST['postvariable1']."\n".$_POST['postvariable2'];
$message = wordwrap($message, 70);
mail('email@example.com', 'My Subject', $message);
Take a look at the example for more info:
For instance, you'll need to give it an email address to send the email from.