One of the best things about WordPress is that it is so easy to extend it’s functionality through plugins. Plugins (like the ones I’ve written and host here) are very easy to install and simply get dropped into the folder wp-content/plugins in your WordPress install. Then you need to go to the Admin “Plugins” area and click the activate link for the plugin. In most cases that’s all you have to do. Two of the best plugin search areas are: http://codex.wordpress.org/Plugins and http://wp-plugins.net/, and contain a large variety of things that you may find useful for administering or setting up your site. I check these on a frequent basis, you never know what might get developed.
One word of caution: Make sure that the plugin will work properly with your version of WordPress. Many plugins developed before the 2.1 version of WordPress may act erratically since they’ve changed some things between versions. If at all possible test out things on a non-production version of your site first.