Replace
<option value=" steve ">steve </option>
<option value=" paul ">paul </option>
<option value=" john ">john </option>
<option value=" info ">info </option>
with (spaces removed)
<option value="steve">steve</option>
<option value="paul">paul</option>
<option value="john">john</option>
<option value="info">info</option>
replace
mail("MYEMAIL", $subject, $message, $from);
with
switch($attn){
case 'steve': $to = 'steve@mydomain.com'; break;
case 'john': $to = 'john@otherdomain.com'; break;
case 'paul': $to = 'paul@samedomain.com'; break;
default: $to = 'steve@mydomain.com, john@otherdomain.com, paul@samedomain.com';
}
mail($to, $subject, $message, $from);
A more efficient method may be to store the addresses in an array and match the key to $_POST['attn']
i.e.
$addresses = array('steve' => 'steve@info.com', 'john' => 'john@paul.com', 'paul' => 'paul@ringo.com');
$addresses['info'] = implode(", ", $addresses); // all addresses
if(in_array($_POST['attn'], $addresses))
$to = $addresses[$_POST['attn']];
else
$to = $addresses['info'];
mail($to, $subject, $message, $from);
You should also sanitize your $_POST data before using it and supply the proper content-type in the mail headers.
All code is untested.