I'm not sure why keyboard viewer would not be an option for you. Go to System Preferences & open the International Preference Pane, click on the Input Menu tab & click the box next to Keyboard Viewer. This will make this available in your menu bar by clicking the flag icon. Select "Show Keyboard Viewer" from the flag menu & you will see a layout of the keyboard. You can then hold down the shift key, the option key OR shift + option to see all the possibilities. The highlighted ones are the accents than you can apply to letters. To get "é" type option-e (nothing will appear or you will see a colored spot), then type e. This accent could be place over most letters. You can change the font in the drop-down menu. Not all fonts will have all characters. Keyboard Viewer places the typing directly into the top, open document.
While you're in the International Preferences, also check to show Character Palette. You can then access it from the flag menu as well.
