Here is a great website on the history of music with cd recommendations:

http://www.unf.edu/classes/medieval/medievalmusic.htm

Here is a quote from it regarding early Christian music. It is amazing, but St. Augustine is talking about the same kind of rules of chant followed by a church reader today (both our two oldest sons and my husband are learning how to read in church):

Early Christian Music

The history of modern western music can be traced directly to the music of the Christian church of the early medieval period. Although annotated manuscripts only date from the late Carolingian period, they already represent a developed tradition. The interesting question, then, is where did early Christian music come from?

 

Like the Jewish communities from which they originated, Christians sang psalms (although not, apparently, in the eucharistic liturgy until the 4th century), but from the earliest days they also seem to have sung hymns, several of which are embedded in the New Testament. The earliest Christian music to survive is a Greek hymn to the Trinity found about a century ago among the Oxyrhynchus papyri. There is an agreement that it represents some form of Egyptian musical tradition.

Apart from that, we know that Christians deliberately rejected all forms of pagan music -- music for the theater, ritual music, and music which used instruments and orchestras. What was acceptable was monodic singing of psalms and hymns. The complex issues presented by music are seen in Augustine's reaction to his own pleasure in musical psalms.

Augustine on Listening to Psalms

At other times, shunning over-anxiously this very deception, I err in too great strictness; and sometimes to that degree, as to wish the whole melody of sweet music which is used to David’s Psalter, banished from my ears, and the Church’s too; and that mode seems to me safer, which I remember to have been often told me of Athanasius, Bishop of Alexandria, who made the reader of the psalm utter it with so slight inflection of voice, that it was nearer speaking than singing. Yet again, when I remember the tears I shed at the Psalmody of Thy Church, in the beginning of my recovered faith; and how at this time I am moved, not with the singing, but with the things sung, when they are sung with a clear voice and modulation most suitable, I acknowledge the great use of this institution. Thus I fluctuate between peril of pleasure and approved wholesomeness; inclined the rather (though not as pronouncing an irrevocable opinion) to approve of the usage of singing in the church; that so by the delight of the ears the weaker minds may rise to the feeling of devotion. Yet when it befalls me to be more moved with the voice than the words sung, I confess to have sinned penally, and then had rather not hear music.

Source: Confessions [trans. Pusey.]

And here is a website on ancient Jewish liturgics: http://liturgica.com/html/litJLit.jsp?hostname=null

And early  Christian liturgics: http://liturgica.com/html/litEChLit.jsp?hostname=null

All three of these links would go well for the rhetoric level of the Early Church study plan we are working on.

The study plan we are working on will include a lot of early church patristic writings. Because a lot of people are unfamilar with these texts, it would be helpful to have an introduction. I found one website (nonOrthodox) that can help to offer that: Handbook of Patrology. I do have a strong love for patristic literature. In fact, it was the early Church text on the Martyrdom of St. Polycarp of Smyrna (disciple of the Apostle John), which converted me to Christ. I can only pray for such faith for myself and our family.