I think you've already shopped for the spec'ed car you want, but my father always try's to buy the car on the lot they want to sell. This takes many forms, sometimes it's the really odd combination of extras or one that has sat on the lot for a while. For instance, my mothers T-Bird was that aqua color, that no one wanted unless they owned/wanted to own one of the originals. Our Jeep Commander came with the smallest engine.
Nissan's inventory checker can help you with this. See if a car of your preferred model/extras hangs around for a while, then try and buy that one. It will have higher mileage, but the dealer wants to sell cars that have been on the lot the longest.
Then again, in this economy, you probably don't need to do any this because cars just need to be sold. But the economy will change eventually
