I'm not into this side of the sport.
But wouldn't a sponsor be more local. Like a local shop or hill or business. The shop I frequent, I talk with the guy on FB often and via phone as well, when I'm not at his shop. We also talk a lot about our families and what not, kinda a more personal relationship.
Isn't that the kind of relationship you would need to be sponsored? Someone you get gear from regularly and are friends with and you would then promote his shop/gear at any event you were in???
Just thinking out loud, again not my thing but I have a good relationship with my local guy. I was actually gonna see if he would be interested in hiring my son in the shop to help learn the retail/shop side of the sport.