The latter :) They can be generated right from the beginning. For example, I had games where I found Time Back and Geyser on Montero (as a warrior, phew) around lvl 20, so it is completely plausible that they were simply generated there.

Next game I reroll I'll be shooting for resurrect or a high lvl attack spell like fire rain / geyser right from the start in Debir lol. Do they tend to spawn in the university or the Castle?

So far I've rerolled around 50+ times and have yet to see any high-end spell like time-back / resurrect / geyser / death-star ...etc in Debir when starting. I've been checking the castle / university and houses/cottage. Are you sure that Debir can spawn those spells right from the start?

If so, you must have been insanely lucky to get both geyser and time-back right from the start in Debir at the same time @.@

He said he got them in Montero ;)

They can't spawn right from the start in the lower level areas (debir, scarlet, bolo, rusty). I said they can spawn in debir later on - "Debir can spawn high-grade spells (as well as troops and artifacts) as your quest for the stones goes on, and you get more and more of them."

Funnily, or annoyingly (depending on your POV) I've only ever found one resurrection in my current game - and that was one of the random treasures my dragon happened to unearth.