Based on what algorithm, would you rate your players and determine odds of battle within a league?
Are Leagues or Tournaments coming to Lackey?
You can always use the ELO system used in Magic.
You will find an explanation of that in the Magic tournament rulebook under Appendix C
http://www.rawdealplanet.com/judges/eloratingcalculator.xls
It's labor intensive because you've got to put in everything manually, but it's what we use for Raw Deal.
Also, use Yahoo Groups and their "Database" feature helps out alot. (You'll only want to give admins access to it, to keep rankings from getting corrupted.)