By default, most WP themes use the horizontal navbar to display links to your static Pages. You might be able to play around with your header.php file, and add some links manually there. If you look carefully, you can find the code that generates the automatic horizontal menu system in your header file. Just add new links in the same format, making sure to include any surrounding <div>, <li>, or whatever tags the links are nested in.
For more information on how the horizontal menu system works, see this codex article: http://codex.wordpress.org/Creating_Horizontal_Menus#Creating_a_Horizontal_Menu
This should help you to figure it out. Good luck!