The Streets of NW

I have always wanted to live in England and found London to be one of the most interesting cities I've ever visited.  Because of this what really caught my attention in NW was Zadie's vivid and detailed descriptions of the streets (like those on pages 42-43).  I wondered how she wrote them.  Did she walk down them and record what she saw? Was it all made up? I would like to look at the streets that she gives the most attention to and see what is really there and possibly what the socioeconomic makeup of the area is.