In the small graveyard in northern Aleroth read the tombstones. Jake's tombstone specifically requests no flowers, especially not from his wife. His wife's grave has a pot of flowers on it... Move the flowers over to Jake's grave and he will appear (in a rather grumpy mood).
The other place you can find him in Aleroth is in the cellar of his house, just south of the graveyard. There is a large pile of crates or packages concealing the hatch.
Once you defeat Jake outside of Aleroth, he will be gone for good.
