Ning, the latest startup of Netscape co-founder Marc Andreessen, is looking to get a jump ahead of MySpace and Facebook by giving consumers free tools to create and operate specialised online social networks of their own. The two-year-old Silicon Valley-based company said the new service, to be introduced on Tuesday, allows casual Web users to create, within a matter of minutes, a highly customized social network for one’s friends, family or acquaintances.