Below are a variety of links put together by Mary Savina at Carleton College, with her notes.  Note that some links are dead:

The first two sites have several pictures of soil profiles, with useful accompanying text:

Tuapaka soils and topography, New Zealand

This site has an interesting collection of soil profiles from New Zealand, along with an explanation about how the soils relate to topography.

Soils of Hawaii

This site, a subset of a more extensive U. Hawaii Soils Site, provides a good introduction to soil profile classification, accompanied by soil profile pictures.

Here are links to important soil science and soil conservation agencies:

Keys to Soil Taxonomy

This link goes to an on-line edition of the Keys to Soil Taxonomy, a guide to the current U.S. soil classification system. There's lots of helpful information here about various kinds of soil horizons, soil classification units, etc.

Soil Science Society of America

The SSSA is the professional society for soil scientists in North America. The organization publishes many books and a set of profile slides, the Marbut Memorial set.

USDA - Natural Resources Conservation Service

The NRCS, part of the Department of Agriculture, used to be the Soil Conservation Service (SCS). NRCS publishes soil surveys of agricultural areas of the U.S. NRCS also maintains a national laboratory for soils in Lincoln, Nebraska. Links from the NRCS page should get you to any digitized soils information produced by the U. S. government.

National Soil Information System

For instance, the NASIS is one of the NRCS programs for compiling and digitizing soils data.

Many of the following sites are interconnected. However, there's some unique information attached to each one:

Biological Conservation Sciences Division Soil Survey

This site has some useful definitions and links to other NRCS pages.

Natural Resources Conservation Service Soils Division

This site has some more general information on soils projects at the NRCS.

National Soil Data Access Facility

From this site, you can see the full range of soils data collected in this country. Much of it can be downloaded from this site.

National Soil Survey Center

This site specializes in soil survey data. It has a link to the Global Change Program of the NRCS, which is particularly interesting.

National Soil Erosion Research Lab

The National Soil Erosion Research Lab at Purdue.

United Nations Food and Agriculture Organization (FAO)

This link goes to the home page for the FAO, whose mission includes soils, but also agriculture and food resources around the world.

Canadian Soils Information System

C.A.F.F.E.I.N.E.(Canadian Agricultural Farm and Food. . . )

This site has more links to agricultural and food resources than to soils, per se.

Here are some miscellaneous sites to publications, and "master" sites for soils:

Canadian Journal of Soil Science

New Zealand cybersoils site

Many universities have programs in soils. Here are some links to a few of them:

University of Minnesota's soils home page

Michigan State University
Soil science faculty at Michigan State includes Sharon Anderson, Carleton 1983.

University of Wisconsin

Finally, here's a link for those of you interested in soil mechanics and other aspects of engineering geology:
Geotechnical Engineering Virtual Library

Please let me know about any other interesting sites you find. I'm particularly interested in locating some more sites with good pictures of soil profiles.

Mary Savina