Questionmark.com, a vendor of a test and survey authoring and reporting system actually does have many articles/whitepapers posted on their site.

However, the best resource I've found in writing test questions is from the National Board of Medical Examiners:
http://www.nbme.org/publications/item-writing-manual.html

A few good links there, but I think this really is one of the best resources for really thinking about what you are trying to measure, and how to get to it in the most fair design.

Hope this helps. If you are shopping for systems to deploy tests, please contact me.

Thanks for the question and suggesitons for rsources. Another great resource is Turning Training to Learning. Very practical and simple approach to measuring post training learning and behavior change.