I'm not sure if this will help anyone because it's in Slovak but since you asked...
It's this book http://ved.sk/RC.NS.htm
It's called Return of Slavs in Spirit and Words. There' re also quite many podcast episodes of series Rodná cesta on the internet.
I still haven't read the whole book but if anyone is interested I might start a thread about Slavic mythology. I could sum up book chapters and podcast episodes as I read and listen to them. I think it would be great to have it in English as well because as far as I know, there's very little in English sources about our culture.
BTW it is one of the best conserved ancient mythologies- they had an authentic pagan temple with sacred fire, stone called Ded (Grandfather/Elder) and very old sacred oak tree in Belarus until the beginning of the 20th century!
I'd just like to know if there's one inevitable ingredient- reader's interest