General: about the navigation
Check out the menus right at the top. Often referred to as the "Awesome bar" See: http://moodle.org/plugins/view.php?plugin=theme_decaf
Below that, new in Moodle 2.0, the Moodle menus.
These are some of the main admin functions in Moodle.
Two top menus
Settings for any Moodle component
Finding your "My courses" list
Plus: changing your profile and your password
Inside courses: the "Course menu" block
This is an add-on, it is not standard Moodle. It provides section to section navigation. Click on the links in the menu.