RaHel,
I'm going to help you out a bit. If you click on the "hot links" link at
http://www.interx.net/~zeephi, you will find a link under "Zeta & Sigma sites" for a web site called "Zeta Pages". There one of my Sorors has created a data base of many the Zeta graduate and undergraduate chapters, organized by greek letter. It will take you a while, but you can find out which undergraduate chapters are located in Ohio, and then contact your school directly or the chapter closest to your school.