The following books are standard works on the Monastic life and are readily available from most bookshops.
1. The Cistercian Way Andre Louf OCSO
2.  On being a Contemplative - Ignatius de Pont  
3.  Seeking God. - Esther de Waal
4. The Cistercians: The Way of Simplicity - Esther de Waal
5. The Rule of St Benedict Many translations available.6.  Living with Contradiction - Esther de Waal
7.  Searching for God - Basil Hume OSB
8.   The Rule of St Benedict - Insights for the ages - Joan Chittister
9. The Path of Life - Cyprian Smith OSB
10. The Call of Silent Love DLT - Carthusian Novice Series
On prayer the following may be useful:
1.  Beginning to Pray - Anthony Bloom
2.  Meditations on a theme - Anthony Bloom
3.  Towards God - Michael Casey OCSO 
4.  Prayer  Vols 1 & 2 - Simon Tugwell OP
5.  How to Pray - Andre Louf OCSO 
6.  Personal Prayer According   to the Monastic Tradition - Columban Heaney OCSO
The Bible
The basis of all prayer is Scripture.  There are many daily guides to Bible Study available.  Barclay's Daily Bible Study or 
6 Weeks with the Bible series by Loyola Press are both recommended for those unfamiliar with praying the scriptures.