I can't speak for all GLO's, but my fraternity (it's coed) loves the opportunity to expand. I would suggest returning to those sororities' national websites & contacting them that way. Let them know why you are interested in them, and they will help you from there.
It is a bit of work, but nothing you can't handle. Most school's will require you to have a mission statement & also a minimum number of students planning on participating. As soon as you decide which GLO you want to start a colony as, GO TALK TO THE STUDENT ACTIVITIES DIRECTOR. If you don't do this, you can inadvertantly start a subrosa chapter, and get on the school's bad side from the start. Happy searching & best of luck!
-Carrie
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