One certainly cannot go wrong with pre-Conciliar versions of the Rule of St. Benedict or the Rule of St. Francis of Assisi (the older, the better; I know there are some publications out there of the oldest extant Rule of Francis, but I cannot remember where online I saw them). In fact, any time a traditional Rule can be had relatively inexpensively, such as from eBay or somewhere similar, it is ALWAYS a good thing to get a hold of them. Those rules were written by Saints, and as such are filled not only with the nuts-and-bolts practicalities of monastic life, but also with a DEEP sense of reverence and usually SCORES of references to Scripture and the teachings of Holy Church.
The Life of St. Francis of Assisi, written by St. Bonaventure, is a classic, although some more modern critics have classified it as mere hagiography (more spectacular, fan-boy 'fluff' than actual biography). My take on Bonaventure's Life is that there is bound to be more of the miraculous and supernatural in a book written by a spiritual soul-mate rather than by some academician who worships Kant and Darwin.
The great thing about St. Augustine's Confessions is that the Prots love it, too, so it can be had VERY cheaply... there are literally dozens, if not hundreds, of publishers who have put the Saint's words out for our benefit over the recent decades.
Story of a Soul, by St. Therese of Lisieux, is also a fantastic read. She tells of how she learned to become 'very little and humble', like a child, in her pursuit of a deeper love of Christ.
Another great resource, though not written BY a saint, is Butler's Lives of the Saints. I actually found a leather-bound set that someone had donated to a library that the library was about to THROW IN THE TRASH! It's in near-perfect shape, especially for books printed (this printing) in the 1930s (if I remember right). Every day of the year is filled with the stories of saints, their triumphs, their martyrdoms and their recognition by the Church as the heroes of our Faith.
St. Frances de Sales, pray for us as we learn from the lives of the friends of Christ.
Sacred Heart of Jesus, have mercy on us.