These are the books I declare I have read to some personal impact. The lists ignore many pamphlets, journals (except one series) and web material; nor is there biblical criticism or debates in various faiths. I have much more. The first lot are books on Unitarianism and the second are the theological debate:
Hewett, Phillip (1985) The Unitarian Way, Toronto: Canadian Unitarian Council (and (1976) On Being a Unitarian)
Wigmore-Beddoes, D. G. (1971, reprint 2002) Yesterday's Radicals; A Study of the Affinity Between Unitarianism and Broad Church Anglicanism in the Nineteenth Century, Cambridge: James Clark and Company.
Davies, D. Elwyn (1982), They Thought for Themselves: A brief Look at the Story of Unitarianism and the Liberal tradition in Wales and Beyond its Borders, Llandysul: Gomer Press.
Channing, W. E. (1841) The Works of W. E. Channing D.D. With an Introduction, New Edition, London: George Routledge and Sons.
Goring, J., Goring, R. (1984) The Unitarians, Christian Denominations Series, Exeter: RMEP.
Hostler, J. (1981) Unitarianism, London: The Hibbert Trust.
Marshall, G. N. (1980) Challenge of a Liberal Faith, New Canaan: Keats Publishing.
Emerson, R. W. Selected Essays, London: Penguin Books.
McGuffie, D. (1982) The Hymn Sandwich, A Brief History of Unitarian Worship, London: GA Worship Subcommittee
Short, H. L. (1965-1968) 'The Later History of the English Presbyterians', 1 to 9, complete series compiled, Hibbert Journal, Vols. 64-66, numbers 252-263, London: The Hibbert Trust.
Bolam, C. G., Goring, J., Short, H. L., Thomas, R. (1968), The English Presbyterians: From Elizabethan Puritanism to Modern Unitarianism, George Allen and Unwin.
Hill, A. (No date), A Liberal Religious Heritage: Unitarian and Universalist Foundations in Europe, America and Elsewhere, Unitarian Publications.
Holt, R. (1952), The Unitarian Contribution to Social Progress, London: Lindsey Press
Lyttle, C. H. (1952), Freedom Moves West: A History of the Western Unitarian Conference 1852-1952, Boston: Beacon Press.
McLachlan, H. (1934), The Unitarian Movement in the Religious Life of England and its Contribution to Thought and Learning 1700-1900, George Allen and Unwin.
Manning, B. (1939), Essays in Orthodox Dissent, Independent Press.
Martineau, J. (1891), Essays, Reviews and Addresses, Vols. 1-3, Longman. [sections of]
Hawkins, P. (1998), 'Transformation and the Unitarian Movement', The 1998 Essex Hall Lecture, Information Department of the General Assembly of Unitarian and Free Christian Churches.
Wilbur, E. M. (1952), A History of Unitarianism: in Transylvania, England, and America, Volume 2, Harvard University Press: Cambridge, Massachusetts.
Lakeland, Paul (1997), Postmodernity: Christian Identity in a Fragmented Age, Guides to Theological Enquiry, Minneapolis: Fortress Press.
Troeltsch, E. (1931), Wyon O. (trans.), The Social Teaching of the Christian Churches, Vol. 1, London: George Allen and Unwin, especially 380-381.
McEnhill, P., Newlands, G. (2004), Fifty Key Christian Thinkers, Routledge Key Guides, London: Routledge.
Hanson, A.T. , Hanson, R. P. C. (1980), Reasonable Belief: A Survey of the Christian Faith, Oxford: Oxford University Press.
Beeson, T. (1999), Rebels and Reformers: Christian Renewal in the Twentieth Century, London: SCM Press..
Pauck, W., Pauck, M. (1977), Paul Tillich: His Life and Thought, Volume 1: Life, London: Collins.
Seaver, George (1939), Albert Schweitzer: The Man and his Mind, London: Adam and Charles Black.
Hebblethwaite, B. L. (1980), The Problems of Theology, Cambridge: Cambridge, University Press.
Ellis, I. (1980), Seven Against Christ: A Study of 'Essays and Reviews', Studies in the History of Christian Thought, Vol. XXII, Leiden: E. J. Brill.
Goodwin, C. W., Jowett, B., Pattison, M., Powell, B., Temple, F., Williams, R., Wilson, H. B. (1861, first published 1860), Essays and Reviews, 8th edition, London : J. W. Parker.
Gore, C. (ed.) (1902, first published 1899), Lux Mundi: A Series of Studies in the Religion of the Incarnation, London: John Murray.
Edwards, D. J. (ed.) (1963), The Honest to God Debate, London: SCM Press.
Robinson, J. A. T. (1963, 1994 imprint), Honest to God, London: SCM Press.
Robinson, J. A. T. (1967), Exploration into God, London: SCM Press Ltd.
Robinson, J. A. T. (1973), The Human Face of God, London: SCM Press.
Robinson, J. A. T. (1980), Roots of a Radical, London: SCM Press.
Robinson, J. A. T. (1979), Truth is Two Eyed, London: SCM Press.
Kee, A. (1988), The Roots of Christian Freedom: The Theology of John A. T. Robinson, London: SPCK.
Edwards, D. L (1989), Tradition and Truth: The Challenge of England's Radical Theologians 1962 to 1989, London: Hodder and Stoughton.
Goulder, Michael D. (ed.) (1979), Incarnation and Myth: The Debate Continued, London : SCM Press.
Cox, H. (1966), The Secular City, London: Pelican.
Green A., Troup, K. (eds.) (1999), The Houses of History: A Critical Reader in Twentieth Century History and Theory, Manchester: Manchester University Press.
Hampson, D. (1996), After Christianity, London SCM Press.
Hick, J. (ed.) (1977, second edition 1993), The Myth of God Incarnate, London: SCM Press.
Palmer, M. (2001), The Jesus Sutras: Rediscovering the Lost Tradition of Taoist Christianity, London: Piatkus.
Sykes, S. W., Clayton J. P. (eds.) (1972), Christ, Faith and History, Cambridge Studies in Christology, Cambridge: Cambridge University Press.
Wiles, M. (1974), The Remaking of Christian Doctrine, London: SCM Press.
Cupitt, D. (1971), Christ and the Hiddenness of God, London: SCM Press.
Cupitt, D. (first published 1972, 1985), Crisis of Moral Authority: The Dethronement of Christianity, was Lutterworth Press, SCM Press.
Cupitt, D. (1980), Taking Leave of God, SCM Press.
Cupitt, D. (1984, 1985 paperback, revised 1994), The Sea of Faith: Christianity in Change, BBC Books.
Cupitt, D. (1989), Radicals and the Future of the Church, London: SCM Press.
Cupitt, D. (1992), The Time Being, London: SCM Press.
Cupitt, D. (1995), Solar Ethics, London: SCM Press.
Cupitt, D. (1986), Life Lines, London: SCM Press.
Cupitt, D. (1987), The Long Legged Fly, London: SCM Press.
Cupitt, D. (1990), Creation out of Nothing, London: SCM Press.
Cupitt, D. (1997), After God: The Future of Religion, London: Weidenfeld and Nicolson.
Cupitt, D. (2000), Kingdom Come in Everyday Speech, London: SCM Press
Cupitt, D. (2006), The Old Creed and the New, SCM Press.
Cupitt, D. (2008b), The Meaning of the West, SCM Press.
Cupitt, D. (2010), Theology's Strange Return, London: SCM Press.
Geering, L. (1980), Faith's New Age, London: Collins.
Shaw, G. (1987), God in Our Hands, London: SCM Press.
Sea of Faith Network (UK) (2001), Time and Tide: Sea of Faith Beyond the Millennium, Alresford: John Hunt Publishing.
Van Buren, Paul (1963), The Secular Meaning of the Gospel: Based on an Analysis of its Language, London: SCM Press.
Freeman, A. (1993), God in Us: A Case for Christian Humanism, London: SCM Press.
Hick, J. (1983), The Second Christianity, London: SCM Press.
Hick, J. (2004), The Fifth Dimension: An Exploration of the Spiritual Realm, Oxford: OneWorld.
Hyman, G. (2001), The Predicament of Postmodern Theology: Radical Orthodoxy or Nihilist Textualism?, Westminster: John Knox Press.
Jenkins, David (1985, originally 1966), Guide to the Debate about God, London: S.C.M. Press.
McFague, Sallie (1993), The Body of God: An Ecological Theology, London: SCM Press.
Wilson, Ian (1984), Jesus: The Evidence, London: Pan Books.
Perry, M. (author), Bock, G. W. (editorial associate) (1993), An Intellectual History of Modern Europe, Boston: Houghton Mifflin, 17-22, 26-31, 36-39, 40-49.
Green, V. H. H. (1952), Renaissance and Reformation: A Survey of European History Between 1450 and 1660, London: Edward Arnold Publishers, 111-29, 139-150.
Beard, C., Intro: Barker, E. (1883, revised 1927), The Reformation of the Sixteenth Century and its Relation to Modern Thought and Knowledge, Hibbert Lecture, London: Constable
Hart, David A. (1993), Faith in Doubt: Non-realism and Christian Belief, London: Mowbray.
Dawes, H. (1992), Freeing the Faith: A Credible Christianity for Today, London: SPCK.
Kennedy, L. (1999), All in the Mind: A Farewell to God, London: Sceptre.
Liechty, D. (1990), Theology in Postliberal Perspective, London: SCM Press.
Lindbeck, George A. (1984), The Nature of Doctrine: Religion and Theology in a Postliberal Age, London: SPCK.
Smith, James K. A. (2004), Introducing Radical Orthodoxy: Mapping a Post-Secular Theology, Bletchley: Paternoster Press.
Rorty, R. (1989), Contingency, Irony and Solidarity, Cambridge: Cambridge University Press.
Holloway, R. (2001), Doubts and Loves: What is Left of Christianity, Edinburgh: Canongate.
Holloway, R. (2004), Godless Morality: Keeping Religion out of Ethics, Edinburgh: Canongate.
Zizek, Slavoj (2010), Living in the End Times, London: Verso.
Sykes, S. W., Clayton, J. P. l. (1972), Christ in Faith and History, Cambridge Studies in Christology, Cambridge: Cambridge University Press.
Cupitt, D. (1979), The Debate about Christ, London: SCM Press.
Cupitt, D. (2009), Jesus and Philosophy, London: SCM Press.
Carpenter, J. Estlin (1949), Life in Palestine when Jesus Lived, London: Lindsey Press.
Machovec, M. (1976), A Marxist Looks at Jesus, London: Darton, Longman and Todd.
Altizer, Thomas J. J. (1997), The Contemporary Jesus, London: SCM Press.
Campbell, Steuart (1996), The Rise and Fall of Jesus: The Ultimate Explanation for the Origin of Christianity, Edinburgh: Explicit Books.
Darlison, B. (2007), The Gospel and the Zodiac: The Secret Truth about Jesus, London: Duckworth Overlook.
Sanders, E. P. (1991), Paul, Oxford: Oxford University Press.
Murphy O'Conner, Jerome (2004), Paul: His Story, Oxford: Oxford University Press.
Davies, Douglas J. (2002), Theology and Anthropology, Oxford: Berg.
Linzey, A. (1987), Christianity and the Rights of Animals, London: SPCK.
Plaskow, Judith (1990), Standing Again at Sinai: Judaism from a Feminist Perspective, San Francisco: HarperSanFrancisco.
Bradshaw, Paul, Spinks, Bryan (eds.) (1993), Liturgy in Dialogue: Essays in Memory of Ronald Jasper, London: SPCK.