While not specifically for journalist, this is one of the best tutorials that I have found for learning the basics of HTML. It provides enough basic knowledge for every journalist to at least have some understanding, but doesn’t go too deep into advanced topics. It is 39 minutes well spent.
"The College of Journalism oversees training for BBC News staff. This website focuses on best practice in core skills, offers an overview of specialist areas, legal and ethical issues, and a style guide. It’s a site about BBC journalism."