It doesn't have to be the pits though. I would start by writing a fund-raising letter on league stationary.
Most larger employers contribute to their workers' activities if asked.
Not seeking full sponsors, but whatever they can contribute. Wal-Mart, McDonalds, Rotary, Kiwanas, Chamber of Commerce, are often overlooked. With people's busy schedules, fundraising needs to accomodate. Try to innovate without re-inventing the wheel. If your goals are realistic, modest and explained, people are willing to help.