Reddit mentions of The Path of Druidry: Walking the Ancient Green Way

There are not actually very many articles about modern druids, there are organization websites like the one for the Order of Bards, Ovates, and Druids and A Druid Fellowship

And there are several good blogs like John Beckett on Patheos, Damh the Bard (a very well known and influential figure in modern Druidry), and the Archdruid Report by John Michael Greer, the Grand Archdruid of the Ancient Order of Druids in America

Thing to remember is that there are three main approaches to modern Druidry, one is as a religion, people who worship gods, perform rituals, so on, those that approach it as a spirituality and therefor don't hold gods or ritual with as much importance and focus more on themselves than outside forces, and then those who approach it as a philosophy, these people might not even be theistic at all, and tend to focus on the physical world rather than the spiritual one. There are people fall in between of course but that's the basic gist of it. You're going to have to figure out where you fall in that before you have a better idea as to what kind of information and guidance you're looking for.

A few books you could look at are:

The Path of Druidry

The Druidry Handbook

Bonewits's Essential Guide to Druidism

A Brief History of the Druids

It's important to try and read something like that last book especially to give you some sort of context as to how and why modern Druidry came to be. It isn't an ancient religion, we have no ties to the ancient Druids, and very little knowledge about them at all. So to avoid looking foolish, I'd suggest definitely reading something about the history of the Celts and the Druids, and the modern movement.

Also, spiritual ecology books are a good supplement, Druidry is focused on nature so of course learning about nature, ecology, biology, and such is only going to help you. My two favorites are Spiritual Ecology: The Cry of the Earth and Mystery Teachings from the Living Earth: An Introduction to Spiritual Ecology