The WP Google Fonts plugin allows you to easily add fonts from the Google Font Directory to your WordPress theme.
A simple plugin that lets you use and customize (in real-time!) any fonts from Google Fonts on your existing WordPress site.
Google Fonts For WordPress is a plugin which allows fast and easy add new Google Fonts to your website. You can use them in your visual editor.
Fontific allows you to use Google Fonts on your WordPress website.