A new book is out which may be of interest to readers which examines divination and theurgy in Neoplatonism. The book is authored by Crystal Addey and a full review (by Ilinca Tanaseanu-Doebler) was recently posted at the Bryn Mawr Classical Review.
Here is a brief excerpt of the review:
"The study offers a good overview of the ongoing discussion about ritual and religion in early Neoplatonism. Its perspective offers a fresh approach to the general question of theurgy and philosophy by focusing on a specific complex of ritual practices. Thus, it enables a more nuanced discussion and a better understanding of the detailed workings of Neoplatonic discourse on rituals."