See the "related links" section below for many unofficial fan-made Demi Lovato fan sites. Demi Lovato also has an official fan club website DemiLovatoFanClub.net, however viewing this website requires a paid membership.
$10 for sideline referees and $15 for the center referee per game. That is how much they usually get paid. This is a vague answer. How much you get paid depends on your organization. The higher age group you do the more you get paid.