University of Illinois
University of Illinois: Integrated Pest Management
Allows you to search for many differnt issues concerning Integrated Pest Management. Also allows you to link to related sites.
Other
National Integrated Pest Management Network
This site shows general info on IPM, but allows you to get specific by picking a pest or a commodity.
McGill University
Mc Gill U.: Integrated Management of Apple Pests
Site describes rusts(which are a type of fungus)on apple trees, discusses the disease and how to treat it.