Recently jumped on the Canon rebate promotion which ends Jan 31. Getting $400+ back. Compared prices @ Amazon, B&H, Adorama, BuyDig/(Beach?), and Digital Foto/( Focus). Of course Amazon offers free shipping and their own $15-150 electronics rebate promo which ends Jan 16. B&H and Adorama are well regarded and have excellent very informative web sites, and fair shipping. BuyDig, Beach and DigitalFoto had some great prices but you have to watch out on their shipping fees, particularly DF's fee structure. Their web sites were so so; BuyDig and Beach didn't list if the Canon 70-200 included the Lens Hood and Pouch, and their email suggested I call. Digital Foto sent only half my order but I didn't know that until the package arrived that the rest was on back order. I cancelled the rest of the order which they confirmed on Jan 10 but my CC has yet to be credited Jan 14.
Free shipping from Amazon has been very fast. BuyDig was quick as well.