No Mesmerize Spell tome in Lightgrove ?

[Hanni]

I tried to get my hands on a Mesmerize III Spell tome and read there was one in Lightgrove, but I there was none.

Was this changed ? Does anyone know ?

[Nomnom Victory]

It's still there it's just hidden well.
In Lightgrove there is a spiral stone staircase down the passage on the left at the bottom of which is water, swim down here into a new room where you'll find the Mesmerise III tome along with a circlet of limbo and an enchanted sword.

You're supposed to find that location during a quest but it can be discovered at any time with some searching.