Man, I'm jealous - that Castlefest looks so cool. If ever get a chance to go to Europe I'll have to time it so I can go to that.
Yeah, it is something I've been interested in for a long time. I'll definitely pick up an album soon. I love music that blends old and new elements like that. Do you know of many other bands doing this sort of thing? (Hopefully I'm not derailing the thread too much).
You should definitely try to make it at least once, it is an amazing experience. If you can get the airfare early enough it usually costs me under 1k then it's only around $75 for the festival and camping and then food and drinks.
There are a bunch of old school metal bands that have put out great folk albums, Månegarm's Urminnes Hävd (The Forest Sessions) is pretty great.
As well as Dornenreich's In Luft geritzt