Huh? I don't know what you mean by "land". In St. Petersburg you buy workers, buildings, aristocrats, and upgrades. Which of these are you referring to as "land"?
Oh...sorry... thanks for the feedback! By "land" I'm referring to buildings, which wise players tend to ignore at the beginning of the game. Note, however, that you can replace one building with another... in that case, you did NOT buy new a new "plot of land", even though you did buy a new building.
Does that help, or am I still hopelessly vague?