THE LITURGY OF THE HOURS
To pray the Liturgy of the Hours, you will need your own prayer book(s). In buying them, you will have two basic options: the one volume abridged version, called "Christian Prayer", or the full four volume Liturgy of the Hours set.
The ultimate difference between the two is in the Office of Readings. If you desire to pray/read the Office of Readings, you will need the 4 volume set. The Office of Readings includes a complete year’s worth of daily readings from Scripture and the Church Fathers that correspond to the Church calendar.
However, if you intend only to pray Morning and Evening Prayer or maybe add Midday and/or Night Prayer, you will only need the one volume version. This edition is so easy to use that our 6 year-old son manages it by himself during our daily prayers.
Most people end up buying Saints’ biographies and Bibles anyway, but tend to have a hard time bringing them all together into a profitable routine of personal devotional reading. Instead of that, it may be best to buy the four folume set and make the Office of Readings your primary source for daily readings on the saints and the Scriptures. You can always read more if you find the selections leave you desiring more, but we tend to "bite off more than we can chew" when it comes to starting devotions. This is why the Office of Readings is so helpful.