Reformed Forum has an excellent 
interview with Babara Duguid on her book, 
Extravagant Grace. 
Click over and give it a listen. I think highly of this book, 4.5 out of 5, and heartily recommend it.
Book recommendations:
"People often ask me how it is that my faith has become so 'gospel 
centered' and I always respond, 'I had a group of friends who kept 
teaching me about Jesus, even though I didn't want to hear it.' Barbara 
Duguid is the primary friend to whom I owe greatest thanks for her 
loving persistence with me. Barbara is qualified to bring you a message 
of extravagant mercy because she has drunk deeply of it herself. She 
knows that, along with John Newton, she is a great sinner who has a 
great Savior and it is this message of God's mercy to undeserving 
sinners that will encourage you to live in the light of the sweetest 
news ever heard: 'He died for a wretch like me!' Buy this book, buy one 
for a friend, and live in the freedom that only the good news of the 
gospel can bring."
—Elyse Fitzpatrick, Author of Idols of the Heart ---
"I
 know Barb Duguid up close, as a friend who with her family swooped in 
to be God's hands and heart to our family in a time of need. Her wise 
counsel was always backed up by a rich experiential knowledge of God's 
amazing grace—and unrelenting compassion. Weaving together the 
delightful insights of John Newton with her own experience—and that of 
many people she's counseled over the years—Barb tells the story of God's
 unrelenting compassion toward sinners like us with profound wisdom. How
 amazing is grace? Like Newton, she has learned well the answer to that 
question from the greatest story-teller of all."
—Michael Horton, J. Gresham Machen Professor of Systematic Theology and Apologetics, Westminster Seminary California "Stay
 away from this book. If you buy it, don t read it. Barb Duguid makes 
idolatry too nauseating, grace too promiscuous, the Trinity too 
omnipotent, Christian experience too diverse, sanctification too scary, 
and sovereignty too comforting. On the other hand, it could be a holy 
temptation... yielding may be no sin."
—Dale Ralph Davis, Pastor, Woodland Presbyterian Church, Hattiesburg, Mississippi "In
 this fine book, Barbara Duguid combines her love of church history, her
 enthusiasm for John Newton, her insights honed as a pastor's wife and, 
above all, her love for Christ and his church. Here the reader will find
 sharp insights into the psychology of sin and sound practical advice on
 how the Bible speaks to the mundane rebellions of everyday human 
existence. The heart is indeed restless above all things; Barbara Duguid
 ably directs us to where we can find rest: in Christ alone."
—Carl R. Trueman, Paul Woolley Professor of Church History, WTS PA; Pastor, Cornerstone Presbyterian Church (OPC) Ambler, Pa.