Duck has summed it up nicely. Basically A&M and Broadway and whatever other names they are using, sell the grey market camera body (just the _body_) for that price. They do _not_ include all of the usual stuff that you'd get in the box (e.g. battery, charger, instructions, warranty, etc). They will offer to sell you the other usual accessories when you call to order the camera. The final total price will be more than if you'd just bought from a reputable place in the first place.
If you really do just want the body (e.g. if you are buying a 2nd body of a type you already have, so you have all the necessary accessories), they will often get all huffy and claim that the camera is out of stock. Check their rating on resellerratings.com. You will not want anything to do with them after that.
It'd be almost as bad as buying a camera off of ebay from a seller with 10 other D1X's for sale ending all within 10 minutes of eachother and with only feedbacks for buys. Run away. Far away. Fast.
I, too, went through the agonizing process of buying a digital recently. I bought a D100 on August 12th, 2002. I, too, considered buying from Broadway (A&M), but ran away after my conversation with them. In fact, I wrote an article about the experience. Here is a paragraph out of my article which is applicable to your question.
<<<< START ARTICLE QUOTE >>>> "Flipping through my Peterson's Photographic magazine out of desperation for new camera stores to call, I found Broadway Photo with an unbelievably low price of only $1649.00. Well, that sounded promising, so I called them up, credit card in hand. The salesman assured me that they had a "good supply" of D100s, both USA and Grey Market versions. I asked him why the price was so low, and he said, "well, you have to buy a few accessories like a battery and charger for only $249.00." I was a bit wary of this, since I had read DPReview's detailed D100 review, and knew that a battery and charger was included FREE with the camera. So, I asked him a very specific question, "What will this camera cost me if you leave everything in the box that came from the factory?" "$2,395.00" was his sheepish reply. Needless to say, I hung up quickly. $750.00 extra for manuals, strap, batteries, charger, and body cap, seemed a bit pricey. Why not just charge a normal price? Hmmm..." <<<< END ARTICLE QUOTE >>>>
To all the people out there that would like to purchase NEW cameras $1000.00-2000.00 dollars cheaper than every other store out from the Twilight Zone please go to E-bay immediatly and purchase some of my "almost new" 35mm film canisters for the low price of $69.99 (free shipping). Name to look for?..............P.T.Barnum@ebay.com