In real estate anything is negotiable, but home builders can be a little tough. The reason is that their profit margins are often not very high, and therefore they don't have much room for deep discounts.
That being said, there are still ways to get a great deal on new construction.
First, remember that the prices in new developments are the lowest when no homes have even been built yet. When there's nothing but mud at the construction site, that's the time when builders are most eager to get buyers.
Second, don't think only in terms of the price. If the builder is unwilling to offer a discount, then ask for upgrades. Builders can be surprisingly accommodating here.
And third, hire professional help. A trusted, seasoned Realtor can help you with all the complexities of a new home purchase. Having your own Buyer's Agent doesn't cost you anything (the commission is paid by the builder), but it can make your home-buying experience easier and far more pleasant.