If you have not yet perused this site, Child Abuse Evaluation & Treatment for Medical Providers is a virtual one-stop for all things on this subject. It’s essentially an e-book, with chapters that are well-organized and easy to read. The site is pretty accessible and plentiful links allow you to delve more deeply into subject matter as warranted. And if you’re helping to train police and prosecutors, some of the charts and outlines would be pretty useful for them, as well. My biggest complaint so far (because I’m still working my way through the site, and admittedly, it’s not my area of specialty) is that some of the resources are out of date (read: IAFN, which according to this link still has us in NJ), or just missing (like NSVRC).
If treating child abuse isn’t your area, but screening for abuse is part of your work, then you might want to check out Stanford’s site. They do a nice overview on child abuse screening (with, coincidentally, links to the aforementioned site). And while some of it is very California-specific, there’s a lot that’s generalizable to the rest of the country. If nothing else, check out their reference page with some great articles organized under topical headings.