I just got a copy of
Then and Now: San Fernando Valley,
a fun collection of photos showing the valley as it was once upon a time, compared to what it's like now. In many cases the editor has found photos taken from the same viewpoint, and on rare occasions the same landmarks are still standing. You won't get a very deep history lesson here; most photos are captioned with only a couple of sentences. But it does provide a great sense of how much things have changed, often within the memory of those who still live here.