It's definitely cheaper if you buy the whole duck, and then you get all that great fat and bones (to make stock with later). I found whole duck at a local "natural" grocery store for under $3/lb, but after doing a little research I discovered that the duck was from a large industrial duck factory in Canada where the ducks are fed primarily corn and soy, have no access to water (or natural food sources), and are kept in pretty cramped conditions. It was very tasty, but I probably won't buy that brand again. A decent sized whole duck at Whole foods is likely to run about $25, which sounds like a lot, but you can get a couple of meals for two out of it in addition to the fat and bones. Breasts and legs can get really pricey, like $15-$20/lb, so I generally only buy those when they are on sale (which is almost never). You might try looking around for a local farm that sells whole fresh ducks.