If you're writing your first novel, I wouldn't recommend this as a resource for learning fundamentals like character development, story structure, etc. I would also suggest skipping almost all the advice on publishing. This was written in 2008 and quite a lot has changed since then, particularly with regard to self-publishing and self-promotion. (She talks about listservs! Old school.)
There is a lot of great food for thought, however, on how to approach your research for a historical novel. For example, she explores the balance between authenticity and believability. It doesn't matter if a particular word or phrase was really in use -- if it doesn't sound like it might have been common in the time period you're writing about, it will pull your reader out of the story. There's a delicate balance between authenticity and accessibility, too. You owe it to your readers to do more than simple window-dressing, but info dumps are going to kill your pacing. As with fantasy, you'll need to slip the world-building in unobtrusively. Along those lines, she talks about some crafty ways to bring real historical figures into your fiction in a believable way.
She also includes specific sources for researching various eras/settings and discusses how to choose details from them that are relevant to your story. Relevance is determined by the context of your character, not just possible interest of the reader. Take horse shit on the street, for example -- she points out that it used to be everywhere! This is gross! For a modern reader transplanted to the historical setting, it might be the very first thing they noticed. If this has always been on the streets where your protagonist is walking around, is it really notable? In a first person narrative, your protagonist may not even notice unless they step directly in it.
Historical context is obviously critical for everything else, as well. Your character's personal details, the circumstances of the mystery/murder itself, how the investigation proceeds... She doesn't include a checklist, but you could easily generate one from her chapters to help steer your research as you plot. She mentions some anachronisms specific to the historical sleuth's work, too. You must be careful not to include the modern POV on criminal psychology, police procedures, and forensics, for example.
So, overall, a good resource for getting started with historical mysteries. I'll definitely pick this one up again for a second read if I write one.