To be fair, I use to chase sponsorship when we did the drag car thing.
I guess ya have to understand, what you want to achieve, has been tried by many, successful for a few and make sure you have a point of difference to entice them to spend some money on you and your outfit.
I was getting in the late 90's early 2000's, I use to get different amounts from different businesses that ranged from $1,500 to $4,000 per year and one bloke would pickup the account for the methanol each meeting.
Good luck.