Add a Facebook “Like” button to WordPress Easily

Your friends spend most of their time on Facebook, so why not take advantage of that on your WordPress site?  Adding a Facebook “Like” button to your WordPress theme is very easy to do.  In this example, we will show you how to add a “Like” button to your posts by editing one file:

Open your theme’s single.php file and add the following code where you would like it to be displayed:

<iframe src="http://www.facebook.com/plugins/like.php?href=<?php echo urlencode(get_permalink($post->ID)); >&layout=standard&show_faces=false&width=450&action=like&colorscheme=light" scrolling="no" frameborder="0" allowTransparency="true" style="border:none; overflow:hidden; width:450px; height:25px"></iframe>

http://developers.facebook.com/docs/reference/plugins/like/#

Note: This one is my own creation.