The Pedosphere and Its Dynamics: A Systems Approach to Soil Science
Online reference book. It explains aspects of soil science e.g. function of soil, soil profiles, soil texture, soil formation, organic matter and the interactions between soil and the air and water.
http://www.pedosphere.com/

Introduction to Soils
Lectures about soil surveys, soil texture, soil acidity and soil fertility. Information about liming, fertilization and soil testing with particular reference to forestry.
http://syllabus.syr.edu/esf/rdbriggs/for345/syllabus.htm

Soil Micromorphology
Sites of interest, books and events related to soil observation at the microscopic scale. Soil Science Society of America, Soil mineralogy div (S9)
https://www.soils.org/divisions/s09/micromorph/

Introductory Soil Science
Lectures and Laboratory Units of the Soil Sciences Courses at the University of Minnesota. Influences on soil fertility are explained and simple soil tests are described.
http://www.soils.umn.edu/academics/classes/soil2125/doc/labunts.htm

Soil
Index and introduction to our large soil section.
http://www.seafriends.org.nz/enviro/soil/

Advanced Soil Genesis: Soil Morphology and Classification
A short introduction to soil morphology (description) and a presentation of the 12 soil orders (US) and their genesis. University of Arizona, Soil, Water and Environmental Science, Craig Rasmussen.
http://ag.arizona.edu/classes/swes541/Lectures/swes541_1_basic_concepts_2.pdf

UK: United Kingdom soil classification system
A short introduction to UK soil classification system. Soil characteristics and soil classes. SoilsWorldwide (National Soil Resources Institute Cranfield University)
http://www.soilsworldwide.net/index.php/United_Kingdom_soil_classification_system

ELE International Ltd
Environmental monitoring and testing equipment for weather, water, soil and agronomics from ELE International
http://www.ele.com/env/int/index.htm

Project Soil
An educational program designed to teach the importance of soil, types of soil, erosion processes, and soil conservation principles. Description of kits and teacher material available.
http://projectsoil.org/Default.htm

Analytico
Provide tests for environmental hazards with chemical analyses of water, soil or air. Testing for 200 compounds with results returned in 5 days.
http://www.analytico.com/