Can we either have a link to your site or a link to the actual theme?
Right now all that is visible is the "Coming soon" page.
Generically, you can edit your menu (if the theme supports it) via
http://www.helpmaryfightcancer.ie/wp-admin/nav-menus.php
Also, as you are running WordPress 3.0 and it's a new installation, you may want to consider starting off with WordPress 3.3.1.