Robin Wolaner, who founded Parenting magazine in 1987, has started a Web site for older people. That is the latest view from Silicon Valley. Technology investors and entrepreneurs, long obsessed with connecting to teenagers and 20-somethings, are starting a host of new social networking sites aimed at baby boomers and graying computer users. The sites have names like Eons, Rezoom, Multiply, Maya’s Mom (where parents share), Boomj (Web community for Baby Boomers and Generation Jones), and Boomertown (They’re searching for adventure. They’re searching for happiness). They look like Facebook — with wrinkles.