the skatepark in greenville north carolina will sponsor you
Start with a product - what are you 'selling' to the sponsors? Do you make videos, have a webpage/blog? Do you do local shows? How much are you willing to sell out? :) Have something calculated and concrete to offer before asking for something back Advertising for the sponsors is a good thing. Now figure what you want from the sponsors: Money, equipment, advertising, space (real estate)...etc. Plan ahead, then make an offer.
Talk to local business owners. It has been my experience that Mom and Pop business establishments are more amenable to supporting local athletic teams.