Parker Brothers - 2004
This expansion is found in Europe (UK for English version), but not found here in the US. The expansion adds the bottom third of the Middle Earth map that includes Mordor and Gondor for the first version of the game (FOTR/TTT). The new US Trilogy version does the exact same thing but it is included on one board. What is different with this expansion is that there is a mini game included that does not come with the Trilogy version. On the newsboards, it doesn't sound as if Parker Bros/Hasbro will publish this mini game here in the US. So if you want it, you have to get the Expansion.
When I find out what the rules are, if they are updated like the Trilogy version, I will let you know. For now, here are some pictures of the game...

The UK LOTR Risk Expansion Box

The expanded board that meets up with the first version of the Risk game. This is pretty much what the Trilogy game now looks like.

Here are some of the new figures that come with the Expansion game.

Here is the mini game that is on the flip side of the board. This is a separate game from the main game.