This looks as though it's rather a hot topic, and "the authoritative" account is not likely to be out there just yet. I haven't done much in this lately , but obviously , with the current arguments being made for reparations for slavery ( articulated well by Ta-nehisi Coates) there are a number of people who'd like to be able to say, "hey, my Irish ancestors were slaves, too. Get over it". This is silly claim: there were obvious differences as to the status and rights of indentured servants / apprentices, compared to African slaves- and, of course, when there was still a great need for field labor on the Chesapeake but the tobacco boom had passed, word got back to England that indentured farm hands would no longer stand a chance of getting rich, in the later 17th c. , and far fewer of them signed indentures or contracts, preferring to take their chances at home. But Africans had no choice: far greater numbers, more and more of them, were captured and sold into slavery, to meet the demand, and it was permanent, not temporary. Any book that blurs the lines, even just a little bit, is going to get a lot of annoyed responses.

When I was last reading in this, Edmund S Morgan's American Slavery, American Freedom was the standard text. I'd say it's still useful, ( and Morgan could really write well) but it's old, now. A newer work is Christopher Tomlins' Freedom Bound. It's a much deeper examination of the whole legal evolution of slavery in the colonies- the creation of a whole structure of laws that would define the institution to the point where the country in 1850 would have two different sets of laws, for the north and the south, an impossible situation that the Dredd Scott decision sought to correct ( by pretty much saying the southern laws applied to the north) and which the Civil War almost resolved. I think that you have to look at indentured servants in the legal context, and compare them to slaves, not just look at them on their own. Otherwise it's easy to get mislead as to their significance.