Where do you get resurrect spell?

[Ryastar]

You get resurrection where ever it ends up being in your game, or nowhere at all. Unless you are a paladin (and therefore start with the spell) you are not guaranteed to find resurrection. The same goes for nearly all spells and things in the game. The location of each is determined at random when you first start the game, and the location can be anywhere, or nowhere at all.

As for the demonis/elven land question, the elven land is before demonis, as in the quest takes you to the elven land first, and the battles there will be easier. It is simply because of how the geography of the game works that you are able to access demonis first.