A good definitions page for service-learning.
http://www.cns.gov/learn/about/service_learning.html This site offers basic service-learning information.
http://www.inform.umd.edu/CSP/ This gives an excellent view of service at the University of Maryland. Of special interest is the service-learning link which takes you to a nuts and bolts page.
http://www.gonzaga.edu/studentlife/ccasl/index.html Gonzaga University's approach to service-learning
http://www.saff.utah.edu/bennion/ The Bennion Center at the University of Utah
http://www.otal.umd.edu/amst/mini-center/resource1.html This is a great site for becoming familiar with options of service-learning implementation.
http://www.nicsl.coled.umn.edu/ This site is from the National Clearing House for Service-Learning and has much to offer if you are willing to do quite a bit of clicking.
http://www.aacc.nche.edu/initiatives/SERVICE/SERVICE.HTM The American Association of Community Colleges controls this site--this particular page is dedicated to service-learning.