Chances are that they are NOT. True, you can get a "refurbished" (used) one at a cheaper price, but they are (normally) only "cleaned up" for repurchase.
I have two laptops: one is an old IBM G41 Thinkpad (used; $199) and a newer Lenovo Z565 (new; $350) both are good, but my Thinkpad's hard drive crashed the day I got it.
My Lenovo still works great (as do the IBM, but it's my secondary system), but I would suggest a new Laptop is a better buy than a refurbished one, simply because you're guaranteed a properly working device when it's new and you are kind of stuck with a lemon if it's used. Plus, the prices are not that severely different.