Well, I'm not sure if I can help you on the fraternity end, but there is a great locals site:
http://www.geocities.com/localsororities
The girl who runs is it great and so organized. If you can't find the information there, you could at least email her (her info. is on her site) and she might be able to help her out. I believe her sorority is in Florida... so ya might wanna try to contact her.
The other thing you might want to try is getting in touch with Loyola University's historical and/or archive department. Most schools have them, and might have information of past sororities and fraternities.
GOOD LUCK...
And by the way, you're right, some locals have been around for ages... My sorority turned 100 years this past Jan!!!!!!!
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