Before you go, read Patricia Monaghan's The Red-Haired Girl From The Bog (ISBN: 1577311906). It's a look at one woman's view of Ireland from a pre-Christian point of view. Even if you aren't a new-ager/Wiccan (which, as I remember, the author is), I think it'll show you another side of Ireland that is really part of the psyche of the Irish people.

I read this not too long ago and it opened my eyes to a lot of stuff in Ireland that might not be right on the surface or in the tourbooks, but no less relevant to understanding the Emerald Isle, its history, and its people.