Sandemans New Jerusalem Tours
Sandemans New Jerusalem Tours has a daily free tour of the Old City (though tips are appreciated). Meet at Jaffa Gate at 11am. The free tour is pretty basic but serves as a great introduction to the city. Try to do this on your first day in town to get better acquainted with the place. More in-depth paying tours (75NIS) go around the Old City and other parts of Jerusalem.