There are two outstanding classics on the subject of conversion: A Call to the Unconverted, Richard Baxter; and, An Alarm to the Unconverted, Joseph Alleine.
Richard Baxter was a bright and shining light in the golden age of theology, the seventeenth century. Not only was he the most voluminous author of his day (72 volumes), but also his shepherding of his flock at Kidderminster was so phenomenal that it stands as a marker for all other pastors and evangelists. He practiced what he teaches in this book. The host of conversions under his preaching testifies to the power of the message in A...

The Reformed Pastor is a most extraordinary performance, and should be read by every young minister, before he takes a people under his stated care; and, I think, the practical part of it reviewed every three or four years; for nothing would have a greater tendency to awaken the spirit of a minister to that zeal in his work, for want of which many good men are but shadows of what (by the blessing of God) they might be, if the maxims and measures laid down in that incomparable Treatise were strenuously pursued." - Philip Dodderidge, D.D.