I would try contacting a few dealers in Vancover or Toronto (Pfatt comes to mind as they are present on AZ).
Glenmore and Royal Oak are owned by the same family and dont deal on any S4. the AB economy is just too hot and I see more S4s around town all the time.
To get a 2011 pretty much fully loaded with low clicks is going to cost you between 45 and 48K. I have seen 2012s listed across the country for 53K+.
These cars are just that good and relatively rare.
BTW if you want a spin in mine come out to the monthly meet @ Original Joes in Quarrey park.

 

I've got a 2011 silver S4, it has just had its 40K service, 6speed manual, push button start, babied since new. Audi care paid for. All black leather interior, carbon fibre inlays, B&O audi, and Navi. It is a lease, but if you are interested pm me and ill get a buyout on the car. or you can take over the lease for another 2 1/2 years....allowed 100k.

 

Took me almost a year of looking for the right deal but I finally was able to find a 2011 S4 with under 25,000 km. Local Calgary car and loaded with every option Audi offers. Got a good deal on it - around the 45k mark. Also came with two sets of tires and rims and the summers are beautiful 19 inch rims.