In terms of recs I think you will be pleasantly surprised about how many alumna you already know! When I got recs for my recruitment I initially thought I would have to go through an alumni panhellenic, but after a quick search of teachers, friend's moms, women at my church, dance teachers, etc. (not to mention family members!) I had a recommendation for every sorority on my campus from a woman that actually knew me well enough to write about specific accomplishments.

I think going in to it with an attitude of, "Oh, I don't know any alumna, do I even need recs?" is not beneficial simply because many many many other women are going to be making the effort to find alumnae.

I am sure that you know some people who are alumnae or various groups - you just don't realize that you do. Women friends of your parents from work, church, other organizations, etc are places to look as well....if oyu find one who is, she'll probably know others....