I used www.etronics.com for my Denon 3802. Got it for way less than Good Guys would sell it for, as well as added a three year warrantee and shipping charges and still was $350 (or more) less than GG wanted.
I usually try Yahoo Shopping for starters as it will sometimes provide a list of places and prices for a specific product. I've had good success. You might want to also look at www.audiogon.com - they do sell some brand-new stuff and even though the selection is limited, the prices are sometimes very good.
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