How can I reach any of the sightseeing bus station from pudong Int'l airport ?

Well, you can take subway line 2 at the airport, and get off at People's Square Station, Exit 19. After arriving, walk to the sightseeing bus directly. The name of the bus stop is Nanjing Road Pedestrian Street (West). The address is no.68, West Nanjing Road. (the opposite of New World Department Store).