help?????

that is a huge question!

Here are some other basic ideas that might give you a head start:
First think about what the "normal" arts organisation does:
- looks after the financial aspects - ie gov funding, business sponsorship, budgets etc
- marketing
- employs artists
- and generally co-ordinates activities of organisation ie lets the artists focus on the arts rather than the admin.
(in no particular order!)

But then they also:
- allow artists to be involved in big plays with big budgets (and therefore exposed to other great artists)
- lobby for the arts cause
- increase awareness in the public of the arts in general. ie its great to have heaps of arts organisations creating a hub and creating arts awareness (breaking down negative perceptions non-arts attendees may have)

hmm thats all i can put together off the top of my head . . . hope it helps!