Several institutions have created wonderful tutorials and videos. Following are links to some of the best available. (Please note that any references to account information, course setup, contacting the helpdesk, etc., on these pages refers to the originating institution, not to Hamilton College.)
Blackboard has an On-Demand Learning Center with video tutorials of many processes.
Hamilton has a subscription with Lynda.com, an online software training site which has a large number of Blackboard tutorials. Please contact the Help Desk (4181) to get a user name and password for this site.
Florida Atlantic University has an extensive Blackboard tutorial, broken down into easily-followed steps.
USC has an extensive selection of Blackboard Tutorials for both faculty and students.
Montclair State University has a nice set of Documentation and Videos for instructors.
Fort Hays State University has a set of recommended practices and tutorials in their CTELT.
And don't forget the Instructor's Manual, accessible from any course (via the Control Panel, Help section).