Here’s a little useful sample to get a link to the newest(latest, freshest… you get the idea) post in WordPress.
Here is the tiny but useful bit of code:
$latest = get_posts(array('numberposts' => 1));
$url = get_permalink($latest->ID);
echo "<a href='" . $url . "'>Click here and read our latest post!</a>";
Yeah, that’s it. Have a great day!