You can take an online tour of the White House. Now I've taken a real tour of the White House and I have to admit that this is just as good. Since you have to stay between the lines, never stop moving, etc., you never really get to see anything! Which makes sense in a way since would you want people traipsing through your house continuously? And I took the tour pre-9/11 so the security is probably now even worse.
From the White House Historical Association website here are some fun facts about the White House (all quoted):
President Harry S. Truman referred to the White House as a "glamorous prison," the "great white sepulcher of ambitions," or the "taxpayers' house."
Nancy Reagan said that about a month after moving in to the White House, she was surprised when the usher sent up a bill for their food. "Nobody had told us that the president and his wife are charged for every meal, as well as for such incidentals as dry cleaning, toothpaste and other toiletries."
It takes 300 gallons of white paint to cover the exterior of just the residence portion of the White House (center), excluding the West and East Wings.
The construction of the White House started in 1792 and was first occupied by President John Adams in 1800. The total cost was $232,372.
The White House was the largest house in the United States until after the Civil War.