I've done this for a few years.............That said and agreeing with the others, you need to get some sponsor's. LQS, JoAnn's, Hancock's or even Hobby Lobby. The biggest sponsor for one fair, was the Guild I was in, I got them involved and they sponsor a $50.00 gift card with a "Very BIG" basket of notion's, fabrics etc.... donated from members. This county fair was like this one till about 2002, now, the quild does the basket, they get sponsor's for Adults, Seniors, Beginner's and Youth places , Best of Show and People's choice. Choose a Judge from another county or out-of-area. It is easier on them and your particpants. Work with your local and area newspapers. And your FCS (Home Ec Dept) at Jr & Sr High Schools, specially if the teacher is a quilter - the youth would love to enter and volunteer to assist your group.
In my past life I was a Extension Agent, so I have loads of suggestions and been apart of local county and state fair's for year's.
You can even contact Ginghar scissor's and a few of the big-name fabric companies to help with prises. Don't be afraid to go as far as 100 miles from your town for sponsor's, the participant's probably drive somewhere to get fabric and such and it just gives you alittle more possibilities for assistance.