Yes, fairy faith paganism is a thing. Actually there are a fair number of us here on Tumblr. So yeah, Tumblr itself is a resource.
The main thing is to start doing. That could mean leaving out snacks for the fairies. Fairies like food that is made by humans. They have dominion over growing things, but breads, cakes, crackers, any baked goods, cheeses, beers and wines are all things that they love to have as offerings. They don’t like lemon or lots of salt. Many of them don’t like iron or steel, so glass, plastic or ceramic plates are better. Put the food outside for at most 24 hours. The fairies eat the essence of the food, and then it should be composted, because compost is something they appreciate.
As for readings:
I would start by getting the Living World of Faery and Earth Light by RJ Stewart. Both are available on http://www.rjstewart.net bookstore for very affordable prices and free shipping in the US.
I also highly suggest picking up a Rudyard Kipling’s Puck of Pook’s Hill which is very affordable in paperback and free for e-readers. Its a novel that is just full of fairy faith lore.
Some people important to Fairy Faith:
Any books by or about them are helpful. There are a lot of poorly written books out there too. Usually if it has a cutsie fairy with butterfly wings dancing about on flowers on the cover, its not your best resource.
I have a lot of posts on this subject, under my tag fairy faith that might be helpful.