Teamwork Learning Skills for Collaborative Work (submitted by Amy). It has a ton of good information on teamwork (i.e. teamwork, team conflicts and problem solving, project management, etc) that might be useful for you.
Willard "Ideas on Teams and Teamwork" -- this is like a Barlett's quotation guide to popular teamwork concepts. Bob Willard, a manager at IBM Canada basically read 40 management books, excerpted key concepts and quotes, and organized them by team factors such as leadership, teambuilding, etc. Provides all sorts of quotes, analogies for lecture slides, etc. Invaluable resource.
Teamwork -- Excellent website on team dynamics by a class at Clemson.
Center For the Study of Work Teams -- excellent site at the University of North Texas that contains extensive bibliographies, research papers, discussion groups about teams and teamwork. Has a big list of other useful links too.
Teambuilders Plus -- consulting firm with nice website and lots of links
Center For the Study of Group Processes -- similar to the UNT site, it's more general about groups. Also has bibliographies and links.
Self-Directed Work Teams (SDWT) -- a site dedicated just to this popular concept in manufacturing. Has some case studies on Harris Corporation and Saturn and other links.
Team Center -- this commercial website has an extremely extensive bibliography on teams and teambuilding -- over 200 articles.
SmallGroups -- a website with lots of small articles on various aspects of small group development (somewhat from a church group perspective).
Group Dynamics: Theory, Research, and Practice -- Speciality journal by American Psychological Association
Laying the Foundations for Effective Teamwork -- Paper by Gerard M. Blair on student teams:
Abstract: "Team skills may be developed in students by lectured instruction on these skills and by explicitly delegating to each team member the responsibility for applying them. This article outlines this approach and reviews student feedback on their own development. "
Why Teams Don't Work -- excerpts of a book by Harvey Robbins and Michael Finley
Basic Managment Skills by Gerard M. Blair - this excellent site contains a series of articles the Professor Blair wrote for IEEE Engineering Management in the early 1990's. There are specific articles on teams and groups, quality on teams, and leadership skills.