I am researching the Augustinians, but am confused and don't know where to start.
It always helps to begin by investigating Falvey's collection of reference works (print and online) as well as the catalog. It will also help if you have an understanding of three important things to keep in mind. Saint Augustine is more the spiritual father rather than a founder per se of the order. So reading biographies of Augustine you will not usually find very much about the history of the order. The modern order, for example, traces its origins to the Great Union of AD 1256, many centuries after Augustine lived (AD 354-430). Another significant fact is that there is a Rule of St. Augustine (so called) and if one searches the Falvey catalog by subject "Augustinians Rules" this will provide you with some really great books, albeit some are listed as being in the Augustinian Historical Institute (which is located on the upper level of Old Falvey). Lastly the name of the Order changed over time. Before 1969 it was known as the Order of Hermits of Saint Augustine designated by the acronym OESA. Since 1969 its formal title is the Order of Saint Augustine or the Order of Brothers of Saint Augustine (OSA).