Reddit mentions of Russian Folk Belief

I'm far from an expert on this, but I recall from a Russian folktale class I once took that many of the saints of Eastern Orthodoxy more or less supplanted the traditional pagan gods, even in legend. If anyone wants to do further reading, we were using this book by Linda Ivanits as one of our textbooks.

Here's an interesting excerpt from the book about the "double faith" they practiced by merging Christianity with pagan traditions.

http://www.youtube.com/watch?v=zdhKHI1iz3s Awesome stop-motion animation, whether you know Russian or not.
Maybe this book would be interesting to you: http://www.amazon.com/Russian-Folk-Belief-Linda-Ivanits/dp/0873328892

Took a class on Russian mythology, folk tales, and whatnot in college. Dug up the old syllabus, and found some book titles for you:

Russian Fairy Tales by Aleksander Afanasev

Russian Folk Belief by Linda Ivanits

First is a compilation of folk tales, fairy tales, and myths, collected from across Russia and most of them are pretty entertaining. Second is a more academic look at Russian folk tales.

Not sure if this is really what you are looking for, but hopefully it will point you in the direction you wanna go.