BellSouth Corp, yesterday opened its BellSouth.net Internet access service in Atlanta and New Orleans to residential customers. It has offered its Commerce-Link Internet service to business customers in those cities since July, but now plans to open residential service in eight cities – Raleigh, Miami, Orlando, Jacksonville, Charlotte, Nashville, Memphis and Louisville – where it already operates a business service. The service will use a customized version of Navigator from Netscape Communications Corp.