Site Deleted? Please help

While I am admittedly a newbie at CSS and such, I was looking for a way to somehow include an ad into my RSS feed. I went to this website:

http://www.smashingmagazine.com/2008/12/02/10-useful-rss-hacks-for-wordpress/

And was advised to enter this into my functions folder:

“<?php
function insertAds($content) {
$content = $content.'<hr />Have you visited WpRecipes today?<hr />’;
return $content;
}
add_filter(‘the_excerpt_rss’, ‘insertAds’);
add_filter(‘the_content_rss’, ‘insertAds’);
?>”

After tweaking it a bit and adding an image of an ad, when I pressed update, everything was gone.

I can’t access my website or my website administration page at all. I don’t even know how to fix this if my website is seemingly non-existent at the moment. Please help!!