There's an interesting website called Living Places that has a wealth of information on towns and cities across America that are great places to live. Not only that, but they have a rather complete list of subdivisions in St. Tammany Parish. An interesting feature of that website is an extensive list of home architectural styles with pictures. So here are some links:
The website seems to emphasize places and towns that are on the National Registry of Historic Places.
The Fallon House on West 17th Avenue, the oldest house in Covington