Doug, you need to work out sanctioning, thatís probably the most important thing you need to do. A sanctioned event will provide needed insurance. You can sanction with USA Water Ski, WWA, or INT, possibly other organizations too. Last year Hyperlight had a program to sanction events. I sanctioned an event in Columbus this year with USA Water Ski. See the USA Water Ski Grass Root Event information on the following web site: http://usawaterski.org/pages/Grassroots/HostEvents.htm
You also need to firm up your venue, what permissions do you need from any organization (city, owners group, state, US Army Corps of EngineersÖ) associated with the lake. Firm up your connection to the restaurant too. For my event in Columbus I had to file a marine event permit with the city. The city had a number of requirements I had to meet including providing $1M insurance naming the city as an additional insured. I also had to provide additional insured for the boat manufacturer/dealer sponsor. Each additional insured cost the event $50.
Starting a USA Water Ski Grass Roots event from scratch can be challenging. USA Water Ski has specific requirements for trained event staff including Safety Coordinator, Trained Drivers, and Judging. Read through the material at the USA Water Ski web site. That should give you an idea of what you will need to do.
Iím not too far away, in a pinch I could be your safety coordinator but Iíve planned a number of events for next year and have a pretty full schedule. If I could make it up to support your event it would be more interesting for me if we could find a way to add a wakesurfing competition or wakesurfing clinic to your event. I can probably bring prize wakesurf boards for a wakesurf competition.
For sponsorship Iíd first Iíd contact my local boat dealerships.
The event I ran last year was my first. I had help from a lot of freinds and familiy, running the event was a lot of work; for me it was a lot of fun, so much that I'm running or helping with more events next year.
If you want to go forward with an event email me, see my profile for my email address. Good Luck.