Good stuff below. The one is a bit negative, but I suppose it's best to prepare you for that too. Joining an established game is like transferring to a new high school senior year. Everyone has there clique and you've got to decide which one you want to try and be apart of. For the most part though MUD communities are known for being helpful, so don't let a bad situation like that discourage you.

I recommend rolling a human first when testing a new game. You already know how to RP a human, so pressure is off. Consider this a throw away character (although don't be surprised if you get attached to it). Use this human to learn how to interact with others and how to do all the basic stuff. Use this time to read up on whatever information is provided on the different race and class choices and start planning a serious character.

If by the time you are ready to create the 2nd character you find you don't like the feel or history of the game, that's your window to escape. If you like what you see, create that new character and get involved!