Turtle's Weir: Book 4 of the Pipe Woman's Legacy

Webb Curtis has a number of urgent projects on his plate. He's supposed to be studying mediation techniques so he can help his mother negotiate a new peace agreement among the gods. He's also supposed to be tracking down the goddess responsible for his mother's illness - and to do that, he needs to find a new way into the gods' realm, as the Norse Trickster Loki has locked it down while He nudges His fellow gods and goddesses toward the ultimate destruction of the Earth.

But Webb isn't doing any of that. And he can't remember why.

What he needs is a whack upside the head...