Canasta

Case's Ladder: Canasta
League hosts ladder games and tournaments.
http://www.igl.net/canasta/

Eliters
League plays on Yahoo. Includes tournament schedule and statistics.
http://www.eliters.com/games/league/default.asp?lid=canay

New Honor League
League hosts ladder games. Includes rules and sign-up.
http://www.cport.com/~wolflady/NEWHL.html