Good biography of Oliver Cowdery?

[Culper Jr.]

I've been interested in Oliver Cowdery lately; he was there from the beginning and I would love to know more about his personality and motivations. His early role in the church is interesting to me (how far was he in on the fraud? did he believe it at least in part?). Has anyone read a good non-correlated biography of him that they could recommend? Or is he discussed in a book that is not necessarily a dedicated biography that may give some insight?

[Emower]

I have been trying to read more about Oliver. He was in on it. What is confusing is that after his break with the church he did confess that he was ashamed to have been involved, but he never did blow the lid clean off of anything.
Enoch Witty in my post about Joseph being a con man mentioned Oliver having a law practice. That definitely played a part in what he was willing to do. Also, how hard is it for us to leave the church nowadays? It probably would have been worse for him.