Columbia Earthscape Books: Includes a small collection of geology books, including several on volcanoes. Some books have complete text; others have partial text.
Find Articles: Geology Databases
GeoRef (1785+) Best database for earth sciences; cites research-level articles on earthquakes and volcanism.
Columbia Earthscape Covers the earth sciences, incl. earthquakes, seismology, tectonics, & volcanology.
Putting Down Roots in Earthquake Country: information on earthquakes for people living in California. Includes basic information on California faults, home preparedness, and earthquake survival (Southern California Earthquake Center).