For industry, see above. Any major university, National Institutes of Health, Charles Stark Draper Laboratory, Inc., The Kresge Foundation. Directory of Research Centers, The Foundation Directory, Federal Staff Directory. See the Career Services library and Lippincott Library for sources of names of employers. Federal Staff Directory, State Yellow Book.
Students are often interested in environmental work.
The Complete Guide to Environmental Careers gives a good overview of topic. World Environmental Directory lists thousands of relevant organizations, here and abroad.