- Find a caterer that will work for cost (this is the only hard part)
- find a hall that can be donated (Legion posts are great)
- Find a baker (cakes), balloonery (if you want), florist, supermarket (for paper goods, utensils, tablecloths)
- We also coordinated theme baskets for raffle prizes. They valued so high, it brought in most of our funds. We had a "sports basket" w/ event tickets, autographed memorabelia, etc; a Travel basket; home improvement basket… We made up posters of the raffle baskets and sold tickets prior to the event (as well as at the event) to maximize donations. We made $5,000 our first year and look forward to doing it again next year.

Raffle basket donations means hitting the pavement. Lots of letter writing, phone calls and emails. But for every 10 refusals, you'll get one great donation. It's worth it. Especially if you get others to help you. It was REALLY rewarding too. You won't regret it.
References :
Parent to Type 1

http://www.jdrf.org/index.cfm?fuseaction=home.viewPage&page_id=0DCA5D9B-CC83-EA40-FEFD2202AB830C4D

It sounds like you should get a company or organization to sponsor you, if you don't have a walk going on near you already. If you have more questions you should contact your local JDRF chaper. Just go to the link above and click the "locations" tab.
References :