We begin Cycle A on the first Sunday of Advent, November 28, 2004. with most of the gospel readings taken from Matthew. On the Monday after the Baptism of the Lord, January 9, 2005, when Ordinary time begins we will be in year I of the 2-year cycle of daily readings.
If you “lose track of” the Sunday readings, most gospels in Year A come from Matthew, Year B from Mark (with John filling out the rest of the year, since this is a short gospel), and Year C from Luke. The readings in Lent Year A are specific gospels from John that are meant to be used for RCIA, (and which can be used in any year for proclamation of the word to catechumens); the gospels in the Easter season are from John, and the second reading in the Easter season is from the Acts of the Apostles. during Advent and Christmas all three years, of course there are lots of readings from Luke since he has most of the infancy narrative.
The first reading for Sunday (old testament) was chosen to correlate with the gospel. the second reading (epistle) just goes in order so that almost the entire New Testament is proclaimed, so sometimes it does not seem to have much connection with the other two readings. The daily OT reading also goes in order so that most of the OT is read over the time period.
Your Daily Roman Missal has a table in front with the cycle of daily and Sunday readings (mine goes up to 2010). the missalette in Church for Advent probably will have a little article up front someplace about this also. Your missal, and also your Catholic bible has the Lectionary cycle also.
there is a “master book” called the Ordo which has all this, plus the dates of principal feasts and solemnities (based on the date of Easter) and beginnings of each liturgical season, calendar of saints, for use in determining which readings and prayers to use for the Mass and Liturgy of the Hours. Each diocese publishes its own copy, with local usages for saint days, holy days etc. I just saw the Ordo on line someplace, probably either
catholic.net or
catholic.org, I would guess adoremus also has it on-line.