Gripsport might be able to repair it. Worth asking them at any rate.
The owner is on RB a fair bit too, username = Grip.
I guess if your going to break a steerer tube you want it to be on an impact that dismounts you from the bike. Can't imagine how ugly it would get if you were moving at speed and all of a sudden your front end just goes awol!
Nearly all steerers are now pressed into the crown and usually something that's best not messed with. Just had a peek at SCV and they have pretty good stock of CSUs so your LBS should be able to sort you out. CSU will set you back around the $250-$300 mark and hopefully you have a techno weenie friend who can re-build your forks for you, otherwise you'll have to fork (excuse the pun) out for a service as well.
i dont think gripsport will be able to fix that one, they do steer tube extension but not that kinda extension.
Just a Q Grip, but wouldn't the head tube & top/down tube junction have taken a beating?