Well, i have experience of these things in the UAE, but laws here are often similar. For example, some things that are points of concern in the UAE.

Public gatherings need prior govt approval.
Re-selling alcohol is illegal without a license
Charging an entrance fee is illegal w/o a license
Erecting a large tent needs approval (unless its on your property or in the desert)
Loud music may attract complaints (so you need to be away from where people live)

The most successful way to do it is through an events agency or a hotel. Takes the headache out of it.

A good party i went to in abu dhabi (years ago) was on an island. We hired a boat from the Intercontinental and that included the use of the island. We then arranged for a generator, sound system,solid flooring,lighting etc etc. We sold "all inclusive" tickets.