Mongoose just announced the availability of a new sourcebook about Sommerlund:

The mightiest of nations in Northern Magnamund is fully explored and detailed in this sourcebook for the Lone Wolf Multiplayer Gamebook. Intended as a resource for both games masters creating adventures and players wanting to know more about the land of the Kai Lords, this book covers the people, cities, and history of Sommerlund, from its earliest days of founding to the current trials against the Darklords.