If visitors are complaining that they can't view your facebook fanpage while not logged into Facebook, follow the steps below to make it public.
Access your Facebook page or fan page.
Click the 'Edite Page' button at the top right of the screen.
Click the 'Manage Permissions' link on the left side of the screen.
Make sure that the 'Page Visibility:' checkbox is unchecked and that the 'Country Restrictions' field is left blank.
Make sure the 'Age Restrictions:' field is set to 'Anyone (13+)' or your page won't be visible to Anyone logged out of Facebook.com. It is against Facebook policy to set your age restriction to 13+ if you have 'morilized sexual content' on your page.
If you made changed, click the 'Save Changes' button.