The World Adult Kickball Association (WAKA) has a list of all active leagues broken down by state and city on its website. Registration procedures vary by city and league, but typically involve paying an enrollment fee and providing personal information.
WAKA was formed in 1998 by David Lowry, Johnny LeHane and Jimmy Walicek in Washington, D.C. It was intended to fill the role of social clubs typical of college and high school for young professionals in the area. Over time, the organization grew in popularity and scope, and, as of 2015, oversees kickball leagues in 35 states.
Each official league sets up its own registration process, with some oversight from the main WAKA offices. Leagues operate similarly to traditional sports leagues as the leagues feature specific teams playing matches on a seasonal basis.
Open registration begins at the start of each year and requires applicants to pay an annual fee for participation. This fee varies by league and covers costs for equipment and other expenses associated with the operation of the league. Registrants are able to sign up as a full team, small groups or as free agents. Free agents and groups are placed into existing teams by the league organizers as needed.