I need to know how quickly I should be picking up a new PSU etc for it.
As others have noted, it's probably better to have a PSU already picked out / ordered prior to ordering from BitMain. Your miner will more than likely arrive sooner than your PSU if you ordered today.
Most likely you'll receive your shipment of the Ant before the tracking number, at least that was my experience with Sushi's Group Buy.
This happened to me as well (outside of a group buy). A couple days after I ordered I got a random UPS notification that they would be delivering that afternoon! Though I'm on the East coast, I'm still impressed with BitMain's overall speed.