Studio Arcanis

Hey everyone, I have been looking for information on the kinds of magickal traditions that come from the British Isles, and I have been running into some problems. I've found many sources that talk about various Celtic traditions and the magick of the Druids, yet many sources also say that the true traditions of the ancient Celts are lost, and the ones we have now which claim to be authentic are really not. Does anyone happen to know of any good books/sources on authentic mystical traditions from the British Isles? I'm hoping I can find someone who knows the real deal about this.

I found out semi recently that I'm direcly descended from the queen of a Celtic tribe, so I'm kind of trying to use this information to piece together my history a bit. I have a spirit that has been in my family for awhile, possibly since then, and I'm trying to find out the traditions mainly revolving around things like faeries and the like. Any help would be greatly appreciated!