Around the world, you can find local groups dedicated to showing visitors their home towns and culture. These 'meet the people' groups offer an insight into day to day life that's not found in the tourism brochures. Here are a few web sites to give you an idea of what's available (Preview on hover; New page will open).
In Europe, try Like a Local (Amsterdam, Rotterdam, Barcelona)
In Buenos Aires, try Cicerones de Buenos Aires
In Hong Kong, try Discover HongKong Cultural Kaliedoscope
I've taken advantage of the Hong Kong program and enjoyed it a lot -- I love that Duk Ling ride! Your fellow passengers are from all over the globe, and add a wonderful dimension to the harbour cruise (photo).