I'll put a vote out there for discount tire direct. Best prices I've seen, and they cover all the duty and import fees. It was still cheaper than any price I could find in Canada for my rims. Super fast shipping, and even though they made a small mistake (didn't inlcude hub-centric rings or tire valves), they more than made up for it. Gave me a coupon code good for $50 off orders under $500 or $100 off orders over $500.

 

I have used TireRack for a set of alloy wheels last year. Decent price and quick delivery. I will buy from them again.