OK, in the hopes of getting more people involved I thought I'd write a guide. I won't be doing this all in one go so this thread will be a work in progress.

Getting Started
To get started in Monster Play you simply need your player character to be level 10 or above to gain access to playing as a Creep. To play as a Freep your player character needs to be level 40 or above.

To start playing as a Creep head to a Fell Scrying Pool. There is one on the west side of Bree as well as East Bree, Michel Delving and Thorin's Gate.

Right-clicking on this will bring a menu with a list of 5 different monster characters. Any one player can create a monster character in each of the 5 monster play classes so don't fret about which one to choose as next time you click the Fell Scrying Pool you can select any of the monster player classes that you have not yet tried as well as resume any you have already created.

Additionally, if you have created a monster player character and want to start over you can erase that char and create a new one of that class.

All monster player characters start at level 50. They do not level up but can be enhanced with Destiny Points (more on that later). If you've already started to enhance your monster player character think hard before erasing it as those enhancements will be permanently lost.

Once you have chosen a monster player character you will be asked to name it. Get ready to enter the Ettenmoors you maggot!

This brings me to an important point - your monster player char is not simply you in another guise, it is a totally separate character. The Ettenmoors also exists as a form of separate server. Once in there you will not be on the Kinship, you won't be able to send tells to people in the main game and you will have a separate friends list to which you will add other peoples' monster player characters.

There is one exception to all this though - your Destiny Points (and yes, more later on those, I promise) are shared between your player character and all your monster player characters.

Jargon
Freep - Short for Free Peoples. Applies for NPCs and regular player characters.
Creep - Nickname for NPC and player controlled monsters.