How to Add a new Volume to a Publisher

I can't figure this out. I know how to add a new comic issue to a volume, but how do you add a volume to a publisher.

For instance, Valiant has a new story arc called Harbinger Wars that will feature 4 separate issues that will tie in issues from Bloodshot and Harbinger (Basically like AvX).

How do I go about adding Harbinger Wars to Valiant's list of comics?

@MrPlentl: When you add a new volume there is an option there to choose the publisher.

@RazzaTazz: But how do you add a volume?

@MrPlentl: that isn't a volume, Harbinger Wars is a story arc, to create a new story arc go to Browse>Story Arcs and click the Add New Story Arc button, on the newly made story arc page click edit in the sidebar General Info area to select the publisher.