Notes leading to a Wiki page. These resources were harvested from a discussion on the IT forum. This page is about online assessment in general. If you are just looking to set up something quick and dirty may I suggest using EDMODO. SurveyMonkey, or GoogleDrive (it was docs) to set up an online test. If you are looking for something more elaborate, then setting up a Moodle or using some of the tools mentioned on my building an online course page might be more appropriate.
Links
http://www.listserv.uga.edu/archives/itforum.html

Lin Zhang suggested:

Laura O'Dwyer's work. Her page is at http://www.bc.edu/schools/lsoe/facultystaff/faculty/odwyer.html
Michael Russell. He has done a lot work relating to technology-based assessment. His page is at http://www.bc.edu/schools/lsoe/facultystaff/faculty/russell.html
Thomas Reeves suggested:

Geoffrey Crisp and Mathew Hillier and their colleagues in South Australia have done some really good work related to assessment in online learning environments. See: http://www.transformingassessment.com/
Tom

Dallas McPheeters suggested
May I recommend some links here: http://www.delicious.com/ChihTu/assessment

Some Books
Recommended by John H. Griffin,
Overall good, ( but not focused on technology):
Palomba, Catherine & Banta, Trudy (1991). Assessment Essentials: Planning, implementing, and improving assessment in higher education. San Francisco: Jossey-Bass Publishers.
Comprehensive, specific, detailed, technology focused:
Khan, Badrul (2005). E-learning Quick checklist. Information. Hershey PA: Science Publishing
Anderson Terry & Kanuka, Heather (2003) eResearch: Methods, strategies, and issues. Boston: Allyn and Bacon.