I would start with my local sports commission / travel and tourism / convention bureau, etc. They have insight into where you could go for sponsors and logistical assistance. If run correctly, it could be a financial success for both the promoter and the athletes. If not, it could be a disaster. The best way to run an event is to concentrate your efforts on the competitive aspects (course, boats, judges, etc) similar to any other tournament. Then, have others involved who know how to create sponsor value, food and beverage, marketing (align your event with a local TV/Radio station), etc. It takes a small army to plan these events and a much larger one to actually execute. Back in day, I was part of the Champion Lake Pro Classic that ran successfully for years (part of the ESPN Summer Nights broadcasts) - even with the assistance of World Sports Marketing handling most of the planning and marketing, it was quite a logistical challenge locally.