Just from my experience as a young haunt... (and a young business owner). I feel like searching for sponsorships is a waste of time. Last year, I put together an extensive sponsorship package encouraging business to split 60 second radio ads with us and combine money to get a better rate... I couldn't get as much as a banner ad. Business owners twice my age looked at me and laughed in my face. I wasted 3-4 weeks of valuable time that could've been spent on the haunt.
My suggestion... if you want to pursue sponsors, come up with a very affordable package... if they don't sell, then give that business tickets to come to your haunt. That way, they might come themselves or even give them to their kids. If they have a good time, you might have a good shot for years to come.
Just my $0.02 don't worry about sponsors, make your haunt over the top and the sponsors will follow. This year, we have several excellent sponsors (none are providing cash, its all networking and in-kind trades)