recommendation letters

what if you don't know anyone who's in a sorority already, do letters of rec have to come from a member of the sorority?

Yes. They need to come from members of that specific sorority. For example, you need a DG alum/member to write you a DG rec, and a Kappa alum/member to write you a Kappa rec.

I didn't know any sorority members/alum when I rushed. But I still managed to get recs for about 10 sororities. You have to network. It's okay if someone you don't know personally writes the rec. It's better than not having one at all.

Ask your mom and dad if they had college friends in sororities. Ask if their friends have siblings/friends who were in sororities. Ask them to ask their coworkers. If they or their friends/children were in sororities. Ever heard of 6 degrees of separation? It's not that hard to find sorority alumni if you try.

If all else fails, contact your local Panhellenic association. But they might not be willing to help you since you waited until the last minute.

You're a little late to the game. Most sororities have already received their recs. You're going to have to do all this networking in less than 2 weeks, and expect your rec writers to write/send the recs within those 2 weeks. Good luck.