I agree with my soror's answer, so please take her advice. To piggyback what she said, A lot chapters are closing for the summer, as well as preparing for regional convention so it's not unusual that you did not hear back from the president.
Since you are new to the area, I would get involved in community service ASAP. There is a HUGE chance that you will run into a soror. Also if you are if you get yourself involved in a local church you will run into a lot of members as well. The best advice is to check out the local chapter's website and keep track of all upcoming events.
Some people say it's harder to join an alum chapter oppose to undergrad because you don't have the advantage of either calling they student activities office inquiring about upcoming events, or you miss out on seeing flyer's posted around campus. I wouldn't necessarily say it's harder but it is indeed a challenge.
Get involved as much as you can in your community. That's the best advice I can give you. If you do that TRUST me you will run into a lot of dedicated sorors.
Hopes this helps!
Diamond-Life Member of Delta Sigma Theta Sorority Inc.