"I'm very interested in Hellenismos. I've read numerous negative opinions on the few 101 books that have been released. In your opinion, what should be the first book that a newcomer to Hellenismos dives into?"
When I started out, I had no idea there even were Hellenismos 101 books and went straight to academic texts. It proved a steep learning curve, but I did rather enjoy the sudden submersion. In general, that is the way in which I take on any new subject: go straight to the hard stuff and let myself be overwhelmed until things click in my head.
Once I finally discovered there were 101 books, I was beyond them and found most of them to be biased towards personal preference and low on general information on ancient Hellas to explain why our modern practices are as they are. Because I had my own personal preference by then, going through modern texts about Hellenismos became grating really quickly. I only read Timothy Jay Alexander's 'A Beginner's Guide to Hellenismos' fully. I have some others but I only leafed through those.
It is my firm belief that when you start out, you should invest in neutral sources. Hellenismos is not standardized. There are huge differences in belief and practice between practitioners from various countries and even between various groups. Learn about ancient Hellas and the ancient practices, then get in touch with the community--perhaps through 101 books--and merge the two. I gave out my source book list a while back, and it's not odd my favourite '101' books are on there as well. Personally, I would say invest in three books (in this order) when you think this might be the religion for you:
Kindt, Julia - Rethinking Greek Religion
Who marched in religious processions and why? How were blood sacrifice and communal feasting related to identities in the ancient Greek city? With questions such as these, current scholarship aims to demonstrate the ways in which religion maps on to the socio-political structures of the Greek polis ('polis religion'). In this book Dr Kindt explores a more comprehensive conception of ancient Greek religion beyond this traditional paradigm. Comparative in method and outlook, the book invites its readers to embark on an interdisciplinary journey touching upon such diverse topics as religious belief, personal religion, magic and theology. Specific examples include the transformation of tyrant property into ritual objects, the cultural practice of setting up dedications at Olympia, and a man attempting to make love to Praxiteles' famous statue of Aphrodite. The book will be valuable for all students and scholars seeking to understand the complex phenomenon of ancient Greek religion.
Mikalson, Jon D. - Ancient Greek Religion
Ancient Greek Religion provides an introduction to the fundamental beliefs, practices, and major deities of Greek religion. It focuses on Athens in the classical period, includes detailed discussion of Greek gods and heroes, myth and cult, and vivid descriptions of Greek religion as it was practiced, ancient texts are presented in boxes to promote thought and discussion, and abundant illustrations help readers visualize the rich and varied religious life of ancient Greece. The revised edition includes additional boxed texts and bibliography, an 8-page color plate section, a new discussion of the nature of Greek “piety,” and a new chapter on Greek Religion and Greek Culture.
Burkert, Walter - Greek Religion
In this book Walter Burkert, the most eminent living historian of ancient Greek religion, has produced the standard work for our time on that subject. First published in German in 1977, it has now been translated into English with the assistance of the author himself. A clearly structured and readable survey for students and scholars, it will be welcomed as the best modern account of any polytheistic religious system.
Kindt's work is easily accessible and is a venerable fount of practical information. 'Rethinking Greek Religion' will help you form a realistic image of ancient religious practices and give you the understanding you need to get through any further scholastic reading. It doesn't tell you much about modern Hellenism, but once you have read this book, you should be able to understand why certain modern practices exist. Mikalson's text is more linear and condensed. It attempts to explain the whole of ancient Hellas in one breath. You could switch between reading either Kindt's or Mikalson's work first, but I have found that it's much easier to nuance Mikalson's words if you have read Kindt's work first.
Burkert is a phenomenon and 'Greek Religion' is quite a step up from the previous two works in complexity and academic speech. Still, in his attempt to make an exhaustive whole out of the ancient Hellenic religion, Burkert provides a framework to base a practice off of like no other has managed to do before or since. It's a hard read, but so worth it.
All in all, this collection will set you back about $100,-. That's a fair investment, but well worth it, I promise you.