well there's several ways to tackle what you're trying to do. you could use a switch statement like previously mentioned, you could also build an array of states in the United States and use an if statement with in_array or array_search to check if the $State variable is in the US or not..
some pseudo code off the top of my head...
$america = array("AK","AR","MI","TX","LA","VT","NY");
if (in_array($State,$america)) {
// address in america
mail($emailSend, $subject, $message, "From: $EMail\r\n");
} else {
// address outside of america, or not valid input
mail(<whatever>,<whatever>,<whatever>,<whatever>);
}
you should probably also use some combination of javascript or some other form validation to make sure your $States variable isn't getting filed with bogus values before you process your mail routine. also be sure to note that in_array is case sensitive if you go that route...
good luck!