Some people don't understand the concept of building a car up and admiring it when it's all done with a major sense of accomplishment. Yea anyone can take their car to a shop and pay someone, btu when you actually rebuilt a car up, it feels so good when it's all done. Id say try to find a shell or one with problems for cheap and build it up. I know a lot of honda/acura parts are interchangable also(not saying they are on the nsx but i bet you'd be suprised, obviously not body parts). but anyways I bet if you just look around you'll find what you need. Good luck.
Bad advice. Building a respectable NSX out of a "shell" will break the bank. It's not worth the time or money. You may feel good about the accomplishment, but your wallet will feel much, much lighter.