You might want to look into using what we call a "Content Management System" - where you don't have to worry about these types of things in the backend.
Check out Drupal
http://www.durpal.org
or Joomla
http://www.joomla.com
Both are amazing CMS driven websites you can have setup within 10 minute, a fully functioning site without the need to mess around with PHP.
Not to mention - expanding on the usability and applicable scenario's of said CMS is simple with the 'Modular Integration' they offer.
Otherwise, handling mail in PHP is fairly easy.
Above you can see we have created a form. the 'action' declares what to do when the 'submit' button is pressed. We indicated that we would like the form to run my_mailer.php. The 'method' tells the form what we plan to do, in our scenario we are POSTING the information, alternatively, you could "GET", but we're not "GETTING" anything, we're attempting to "POST" it so it can be sent.
//new file, called "my_mailer.php" -- contents to follow
$email =$HTTP_POST_VARS['email']
$subject =$HTTP_POST_VARS['subject']
if(!preg_match("/\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/", $email)){
//bad email, invoke errors
echo "INVALID EMAIL!!";
//send them back
echo "
Back";
}else if($subject == ""){
//no subject included
echo "NO SUBJECT!!";
//send them bakc to fix it
echo "
Back";
}else if mail($mail, $subject, $message)){
echo "Email sent. Thank you.";
}else{
//generic error - could be the address?
echo "The Email did not send. Please
Go Back and check the supplied information.";
}