Resources
Surfing the Internet for Earthquake Data
SeismoLinks (USGS)
Caltech Seismological Laboratory
Center for Earthquake Research and Information
Earthquake Intensity
Earthquake Education and Resources
Glossary of Earthquake and Related Terminology
Earthquakes and Seismicity
Volcano and Earthquake Resources
Seismology
BBC: Earthquakes
An Interview with Charles F. Richter
What Is Richter Magnitude?

News & Data
U.S. Geological Survey Earthquake Information
Current World Seismicity
Earthquake Data at NGDC
Earthquake News
EarthWaves
FUR Seismological Observatory Online Data
Virtual Earthquake
Real Time Earthquake Bulletin (USGS)
Swiss Seismological Service
The World-Wide Earthquake Locator
Yahoo Earthquake News

Associations & Institutions
Advanced National Seismic System (U.S.)
American Geophysical Union
British Geological Survey's Global Seismology & Geomagnetism Group
Earthquake Engineering Research Institute (EERI)
European Geophysical Society
European Seismological Commission
International Seismological Centre
IRIS Consortium
International Association of Seismology and Physics of the Earth's Interior (IASPEI)
International Institute of Earthquake Prediction Theory and Mathematical Geophysics
Seismological Society of America

California
A Decade of Notable California Earthquakes
Caltech Seismological Laboratory
Southern California Earthquake Data Center
Recent Earthquakes in California and Nevada
Faults of Southern California
The San Andreas Fault
Shakemap
Recent Earthquakes in California and Nevada (USGS)
Los Angeles Special Map
Northern California Earthquake Data Center
Current Earthquake activity in Northern California
Fault Images of the San Francisco Bay Area
U.C. Berkeley Seismographic Station
San Francisco Bay Area Regional Database (USGS)
ABAG Earthquake Hazard Maps and Information
The Seismic System for Southern California (SCSN)
Up-to-the-minute Southern California Earthquake Map

Earthquake Preparedness
Earthquake Hazards and Preparedness (USGS)
Fact Sheet (FEMA)
LAFD Handbook (PDF)
Earthquake Safety Checklist
Earthquake Preparedness Guide