Adorama offers the Tokina 11-16mm f/2.8 ATX Pro DX Zoom Lens for Canon
, model no. ATX1116PRODXC, for $549
with free shipping
. That's $50 under our July mention of this same lens for Nikon cameras (which required rebate hassles) and the lowest total price we've seen. (It's also a current price low now by $50.) It comes with a flower design bayonet lens hood and features autofocus, 1-touch focus clutch, and more.
Note that this lens is designed for Canon DSLR cameras with APS-C sized CMOS and CCD sensors, not designed for cameras with full frame sensors such as the Canon 5D or Canon FF 6D.