You can download a copy of the Mighty Empires rulebook (a 16.8MB PDF) from the Games Workshop website

The Map

The map with the starting realms marked

If you really want to you can download the full sized version here (2.6MB file).

Clockwise from the top the realms belong to the dwarves of Kol Ankor, the Bretonians of Alors, The Beastial Realm of Lord Morgor, Nueva Estalia and the Land of the Cleansing Fire