I'll definitely have to look up that Walton later on. Though i had some problems with certain aspects of her retelling of the Mabinogion (then again, I have certain problems with the Mabinogion itself here and there
) there were other things about it liked quite a lot. I also enjoyed her novel,
Witch House, though I felt the final portion was a bit of a let-down (too explanatory, dissipating the atmosphere).
I do see a one-volume edition of her Mabinogion novels around a fair amount, so she's either currently or print or at least was so quite recently.
White... It has been quite a long time since I read this, and I never owned a copy of the original versions (though I have read them, back in my teens -- and I definitely prefer the originals in many ways). A somewhat neglected writer, at least by most fantasy fans, these days, and undeservedly so, I think.
(Didn't Lin include the sorcerous battle between Merlin and Mim in one of his anthologies?
Kingdoms of Sorcery or
Realms of Wizardry, if memory serves. That was one of the things which went when he did the revision, if I'm not misremembering....)