I was wanting to know reputable historians who specialize in Ancient Greek Civilization? For example, Bettany Hughes is one, but I would like to know some more.
And if you can sacrifice some credibility for entertainment, Herodotus.
Also, not historians but I really recommend reading Homer, Hesiod, Aeschylus, Sophocles and Euripides to get a grasp of their world.
Wikipedia Category Scholars of ancient Greek history has 43 names of modern historians in it.