horrified at officials

[Nevadaref]

Since we are talking about AAU officials, how do those of you who work these games get assigned them?
Is it just proximity to the tournament and through your local assignor? Does the tourney organizer select officials or do they pick an assignor who can get them a bunch of local guys to cover the games?
Does AAU have a central office, website, board?
I worked one AAU tourney out here last summer and it was done through one of the local HS officials.