The Medical Examiner, by Toney Allman, from the Crime Scene Investigations series.
Yes, it's often filed under Juvenile literature but it gives such a good grounding in the work of a Forensic Pathologist, or Medical Examiner, at a crime scene and in the autopsy room. It also gives information on livor mortis, rigor mortis, and algor mortis and the stages of decomposition of the body. True, you should probably double check your facts (if only because of regional differences) but this should give you enough information to get the first draft out there without making any dramatic story-based mistakes that will need a lot of ironing to get out of the novel. I whole-heartedly recommend this book. I'm even hoping to get a chance to read other books in this Crime Scene Investigations series.