I have read both of those books and I have made the total consecration to Mary. I would recommend this copy of True devotion to the Blessed Virgin:
amazon.com/Montfort-Publications-Devotion-Blessed-Virgin/dp/B004YCVFEK/ref=sr_1_8?ie=UTF8&qid=1308368545&sr=8-8 . I LOVE all the work by St. Francis De Sales, he is my confirmation saint, Treatise on the love of God, and Finding God’s will for you are good books too. I would also reccomend the biography on St. Francis De Sales, here is a link to that:
amazon.com/St-Francis-Sales-Biography-Gentle/dp/0895557096/ref=sr_1_2?ie=UTF8&qid=1308368759&sr=8-2 . I’m about to read The art of loving God by St. Francis De Sales and I’ll let you know how that is when I’m done but I’m willing to bet it’s good too. Once you’ve read True devotion to the Blessed Virgin you should use this book to actually make your act of consecration to the Blessed Virgin:
amazon.com/Preparation-Total-Consecration-Louis-Montfort/dp/0910984107/ref=sr_1_1?s=books&ie=UTF8&qid=1308368970&sr=1-1 . These are my reccomendations, I hope this helps.
*The everlasting God has in His wisdom
foreseen from eternity the cross that
He now presents to you as a gift from
His inmost heart. This cross He now sends
you He has considered with His all-knowing
eyes, understood with His divine mind,
tested with His wise justice, warmed with
loving arms and weighed with His own hands
to see that it be not one inch too large and
not one ounce too heavy for you. He has
blessed it with His holy Name, anointed it
with His consolation, taken one last glance
at you and your courage, and then sent it
to you from heaven, a special greeting from
God to you, an alms of the all-merciful
love of God.