error on POSTed form

I'm having a very hard time trying to add an edited listing to mySQL. I'm
breaking this in to two halves, so that each error/problem can [hopefully]
be pinpointed.

The edit form queries mySQL and fills in a form with their existing
information (identical form to the original "Add Me" form, but this time
echo'ing the data currently in mySQL). This part works great. Once they
have edited their information, Submit takes them to a page called save.php.
Now the problems start. Below are my errors, followed by the section of the
code to which they are referring. The errors are all fields where checkboxes
were UNchecked -- the variables that were checked are not cited as errors.

Warning: Undefined index: hair in /home/httpd/httpdocs/html/save.php on line
33
Warning: Undefined index: tv in /home/httpd/httpdocs/html/save.php on line
36
Warning: Undefined index: film in /home/httpd/httpdocs/html/save.php on line
37
Warning: Undefined index: bridal in /home/httpd/httpdocs/html/save.php on
line 39

My code, beginning at line 20, is:
<?PHP
error_reporting (E_ALL);
$firstname = (ucwords(strtolower(trim($_POST['firstname']))));
$lastname = (ucwords(strtolower(trim($_POST['lastname']))));
$city= (ucwords(strtolower(trim($_POST['city']))));
$state= (strtoupper($_POST['state']));
$country= (strtoupper($_POST['country']));
$availability= (addslashes($_POST['availability']));
$experience= (addslashes($_POST['experience']));
$email= (strtolower($_POST['email']));
$website= (strtolower($_POST['website']));
$newpasswd = ($_POST['website']);
$makeup = ($_POST['makeup']);
$hair = ($_POST['hair']);
$wardrobe = ($_POST['wardrobe']);
$print = ($_POST['print']);
$tv = ($_POST['tv']);
$film = ($_POST['film']);
$video = ($_POST['video']);
$bridal = ($_POST['bridal']);
$artistID = ($_POST['artistID']);

FWIW, I have tried the checkboxes both with and without the ( ) around the
$_POST... Do I have to handle anything differently to account for UNchecked
checkboxes, which presumably aren't passed?

Thanx!
Wm