Where to buy 17-55 2.8 EFS lens?

Have owned a Canon 7D for several months now and familiarized myself with it using my much-maligned 17-85mm lens (which I would actually defend on several fronts.)

Am now ready to bump up to the lens I've had my eye on - a 17-55 2.8 EFS. Am looking for recommendations on the best place to buy one. Price seems to hold steady at right around $1100 and even used lenses remain in this neighborhood. I see no reason to buy a previously owned copy if I'll only save a few hundred bucks on such a substantial purchase.

Any recommendations for purchasing new? Perhaps places with better deals on free shipping, etc, but still reputable outfits. (I bought my 7D from B&H here in NYC.)