This WordPress Plugin by Martin Jonsson, gives a site Facebook “Like” Functionality. It enables selection of button alignment:
Choose layout style;
Select if you want the plugin to show the faces of Facebook users who liked a post;
Set it to sound as “Like” or “Recommend”;
Choose the color scheme (either light or dark);
Select the widget height and width
Facebook describes the ‘Like Button’ as: The Like button enables users to make connections to your pages and share content back to their friends on Facebook with one click. Since the content is hosted by Facebook, the button can display personalized content whether or not the user has logged into your site. For logged-in Facebook users, the button is personalized to highlight friends who have also liked the page.
Plugin homepage: http://martinj.net/wordpress-plugins/facebook-like-button/