Hi Hellen,
welcome to this forum
I typed sudoku history into google and it came up with this:
http://en.wikipedia.org/wiki/Sudokupretty much as I expected. Modern sudoku appeared as 'number place' in Dell magazine in the late 70s. Before that there was some sudoku like puzzles in a French newspaper in the late 19th century.
I play sudoku about once a day. Sometimes more, sometimes less.