Check with area municipality/county Parks and Rec depts. They have leagues, they need officials. If they don't schedule their own, they use an assignor. That assignor will also assign other leagues you may want to work, as well. Will probably set you up on RefPay too.
On a personal note - I cut my teeth on men's wreck league ball. On the upside, it's usually running clock action so you can blow the whistle a lot to work on stuff.