I recently finished The Medici Conspiracy by Peter Watson and Cecilia Todeschini. It's good. It's about crooked antiquities dealer Giacomo Medici and the various looters and fronts he worked with.
There is nothing in this book about coins or coin dealers except for a few paragraphs about Bruce McNall, and that part contained an error (calling Athenian dekadrachms 'the world's rarest coin.')
I like to assume that the ancient coins I buy are not looted, smuggled, then fenced half-a-dozen-times to create a confusing trail before reaching the collector. From this book it seems that vases enter the market exactly that way, and are purposly broken and re-assembled as well! I always assumed that a dirty market couldn't exist, that markets self-police and the 'clean' dealers get fed up with the mad profits the looters made and inform on them. I guess that doesn't happen, at least not for Greek vases? I'm still a supporter of a healthy legal market as a way to avoid the excesses of criminals, but the market's self-policing sure failed in the cases discussed in this book.
In recent news, Medici is offering Italy 'Object X' in exchange for stopping his trial. He won't say what Object X is, just that it's really cool and valuable and stuff.