Soil Science Society of America
Geochemical Society
Mineralogical Society
American Geophysical Union
Clay Minerals Society
Other Soils Websites
The 12 Soil Orders
Soil Series Database at NRCS
Soil Chemistry and Surface and Aqueous Geochemistry groups at Stanford University
Synchrotron-Related Sites
Stanford Synchrotron Radiation Laboratory at Stanford University
Advanced Light Source at Lawrence Berkeley National Laboratory
National Synchrotron Light Source at Brookhaven National Laboratory
Advanced Photon Source at Argonne National Laboratory
Stanford Synchrotron Radiation Laboratory User's Organization
XAFS Spectral Library at SSRL
Matt Newville at APS-GSE-CARS has lots of XAS software, and access to a spectral library
Others on the way.
Useful Software
Visual Minteq, a version of an EPA-based program that is an excellent Windows-based application
XTALDRAW (crystal visualization) and XPOW (for synthetic XRD patterns) from Bob Downs at Arizona
American Mineralogist Crystallographic Database at the University of Arizona
AAnalyzer for X-ray photoelectron spectroscopy and Infrared analyses
MINCRYST database of crystal structures
Other Sites