PHP mail function

programming
1 

<?
include("db.php");
$name = $_REQUEST['name'];
$saddress = $_REQUEST['staddress'];
$city = $_REQUEST['city'];
$zip = $_REQUEST['zip'];
$phone = $_REQUEST['phone'];
$cphone = $_REQUEST['cellphone'];
$email = $_REQUEST['email'];
$club = $_REQUEST['club'];
$year = $_REQUEST['year'];
$make = $_REQUEST['make'];
$model = $_REQUEST['model'];
$category = $_REQUEST['category'];
if( $name=='' || $email=='' || $year=='' || $make=='' || $model=='' || $category=='')
{
    echo "You didn't fill out some required fields (Name, Email, Year, Make, Model, and Category) <a href='http://pvchssurvey.com/auto-show.htm'> Please go back </a> and fill them in ";
}
else
{
    mysql_query("INSERT INTO users
    (Name, Street_Address, City, Zip, Phone, Cell_Phone, Email, Club, Year, Make, Model, Category) VALUES('$name', '$saddress', '$city', '$zip', '$phone', '$cphone', '$email', '$club', '$year', '$make', '$model', '$category' ) ") 
    or die(mysql_error());  
    $message = "Thank you for registering for the Park Vista Auto Show, you'll be receiving an email confirming your registration and instructions regarding the Auto Show.";
    mail('$mail', 'Park Vista Auto Show Registration', '$message');
    echo"Thank you for registering for the Park Vista Auto Show, you'll be receiving an email confirming your registration and instructions regarding the Auto Show.";
}
?>

Any reason why this wouldn’t be sending mail, anything I need to enable outside the script?