I am preparing for a PCS to Fort Benning. What site would you recommend for looking at houses for sale?

must_have_air_conditioning.com

If you are a member of USAA or Pentagon Federal Credit Union (PFCU), you get money back by using one of their real estate agent referrals.
As a note, I found PFCU to have some of the best mortgage packages.

base Housing Office usually has a List of recommended Realtors of approved Rentals...
If you Buy.. remember to retain your own Realtor who will work on your behalf... and work around the BS of the Sellers Realtor...