0) make sure you wait long enough, on a slow connection it may take some time for the javascript to load. Make sure you have allowed javascript in you browser and no spyware or antispyware is interfering with it.
1) try with another browser.
2) go to your user preferences and change the setting for wysiwyg editor to none. You will get a basic textarea instead of an 'graphical' editor.
go to opensourcecms.org and try the cmsms demo there. If that still does not give you the editor, you have the problem on your own system. If you do get the editor, it's your (server)install behaving badly.