Kepler's Books
1010 El Camino Real
(http://www.keplers.com/). it's not in the same league as powell's books in portland, but it's one of the last independent bookstores on the peninsula. kepler's is a frequent stop for many authors on book tours.
The United States Geological Survey
345 middlefield road, 650-853-8300. 8am-4pm. the usgs has a huge office in menlo park where you can obtain detailed maps before setting off on an expedition to a remote location.