Here is a short introduction of how Ranking works:
Every new player starts with a basic skill of 100.
If you play against high ranked players with a high skill (above >200), even if you do not win, you can get quite substantial skill points ending up second or third place.
The skill bonus of each game is then added (or substracted) to your base skill, as can be seen in this example here:
http://www.planetmule.com/user-skill/?user_id=103473
So picking the right matches against high ranked players, you can quickly gain a high ranking position yourself without the need for 1000+ games under your belt.
Happy MULEing!