The following are sources that I highly recommend (watch for frequent additions):
Borchert, Gerald L. Responding to Mystery: A Worship Introduction to the New Testament. Morristown, Tenn.: by the author, 2006.
Bradshaw, Paul F. “The Effects of the Coming of Christendom on Early Christian Worship.” In The Origins of Christendom in the West, ed. Alan Kreider, 269-86. New York: T&T Clark, 2001.
Bradshaw, Paul F. The Search for the Origins of Christian Worship: Sources and Methods for the Study of Early Liturgy. 2nd ed. New York: Oxford University Press, 2002.
Clapp, Rodney and Robert E. Webber. People of the Truth: The Power of the Worshiping Community in the Modern World. Eugene, Oregon: Wipf and Stock Publishers, 2001.
Fagerberg, David W. “Divine Liturgy, Divine Love: Toward a New Understanding of Sacrifice in Christian Worship.” Letter and Spirit 3 (2007): 95-112.
Guardini, Romano. The Spirit of the Liturgy. New York: The Crossroad Publishing Company, 1997.
Hurtado, Larry W. At the Origins of Christian Worship: the Context and Character of Earliest Christian Devotion. 2nd. ed. Grand Rapids, Mich.: William B. Eerdmans Publishing Company, 2000.
Mitchel, Leonel L. Praying Shapes Believing: A Theological Commentary on the Book of Common Prayer, Harrisburg, Penn.: Morehouse Publishing, 1985.
Pfatteicher, Philip H. Liturgical Spirituality. Valley Forge, Penn.: Trinity Press International, 1997.
Ratzinger, Joseph Cardinal. The Spirit of the Liturgy. San Francisco: Ignatius Press, 2000.
Schmemann, Alexander. Introduction to Liturgical Theology. Crestwood, New York: St. Vladimir’s Seminary Press, 2003.
Talley, Thomas J. The Origins of the Liturgical Year. 2nd ed. Collegeville, Minn.: The Liturgical Press, 1986.
Webb-Mitchell, Brett P. Christly Gestures: Learning to Be Members of the Body of Christ. Grand Rapids, Mich.: William B. Eerdmans Publishing Company, 2003.
Webber, Robert E. Ancient-Future Time: Forming Spirituality through the Christian Year. Ancient-Future Faith Series. Grand Rapids, Mich.: Baker Books, 2004.
Webber, Robert E. Worship: Journey Into His Presence. Mansfield, Penn.: Kingdom Publishing, 1999.
Weil, Louis. A Theology of Worship. The New Church’s Teaching Series, eds. Cynthia Shattuck and Vicki Black, vol. 12. Boston: Cowley Publications, 2002.
White, James F. A Brief History of Christian Worship. Nashville, Tenn.: Abingdon Press, 1993.
Wright, N. T. “Freedom and Framework, Spirit and Truth: Recovering Biblical Worship.” January 2002. http://www.ntwrightpage.com/Wright_Biblical_Worship.htm (12 March 2007).