If you're looking for a book on what Jonathan Edwards thought about certainty, epistemology, the role of the Spirit, and the role and purpose of apologetics, you probably can't do better than Steve Nichols's An Absolute Sort of Certainty: The Holy Spirit and the Apologetics of Jonathan Edwards (P&R, 2003).
And if you first want an introduction to the ideas in the book, then check out these conference talks from Nichols:
HT: Jeff Downs
