Found this really good entry with bunch of links that are good.

http://www.brightworks.com/technology/adobe_flex/testing_debugging_agile_methods.html

Joe Rineharts entry/tutorial on CF and FlexUnit
http://www.firemoss.com/blog/index.cfm?mode=entry&entry=658DF66B-3048-55C9-43662A44BE6E39A9

Flex Unit w/ cairngorm
http://jharbs.com/blog/?p=96