First on the list, The Bible.
The Art of Prayer: An Orthodox Anthology.
Celtic Daily Prayer: Prayers and
Readings from the Northumbria
Baillie, John. A Diary of Private Prayer.
Carmichael, Amy. Edges of Water.
Chambers, Oswald. My Utmost for His Highest.
Chambers, Oswald. Still Higher for His Highest.
Harter, Michael, ed. Hearts on Fire: Praying with the Jesuits.
Harvey, Andrew & Ann Baring, compiled by. The Mystic Vision.
Lewis, C. S. A year with C.S. Lewis: Daily Readings from His Classic Works.
Merton, Thomas. Through the Year with Thomas Merton.
Tickle, Phyllis. The Divine Hours: Prayers for Springtime; for Summertime; for
Autumn and Wintertime.
"The Upper Room".
Writings from the Philokalia on Prayer of the Heart.