[Hepasto The Terror]

Hard luck dude, spells are random in terms of availabilty. No one can exactly point where they can be got. (unless you are a paladin; paladin gets this spell from the furious paladin in Marshan Swamp ). Throw the staff, get some sword which gives high attack (like dragon slayer which you can acquire after completing the tournament in knights temple)...
and lightning is not a poor spell to be called as simple, its a descent
spell.

Which character are you playing on?

you can use spells like geyser which is far better than lightning. Only for the reason that you have a staff, it does not mean you have to use it... try alternatives.

For any help ask me...