In Australia the national organising body for longboarding is ASRA.
ASRA is a non government funded volunteer organisation. Basically a few dedicated skaters doing a lot of work.
They have a forum, there are annual meetings, there is plenty of scope for parents to get involved and help out. Don't be shy. Don't worry that you dont know anything about the sport because they want skills other than skating: admin, accounting, organising, etc.