Pure_mage, he won't be able to use mail() using something like wamp run locally, and he's probably not even using that since he said he just started :/ Your best bet would be to get some cheap web space, or if your site is already live, create a new document, type:
<?php phpinfo(); ?>
save it as info.php, ftp it to your server and see what it says when you try to view it. If you are asked to download it, or it doesn't have a bunch of stuff on the page, then you need to contact your host to see if you can get php, explore another server scripting language (perl/asp/even jsp) or use a third-party site that would allow you to do this. I'm sure they have them. Oh and, there's no reason to have to validate the email as he's going to have to input it directly, not by form variable. Saves some code =)