Going through some of those lots is a good waste of time, just be glad were not the one's wasting money when the hammer drops
I have this color laser copy of what appears to be a development map for Super Metroid: http://mdb.classicgaming.gamespy.com/sm/smart_devmap.jpg Got it on ebay for very little. Although it's only a copy (it's only 11x17, and you can tell by looking at it that the original was much larger), I did my homework and I do believe that it came from Nintendo. I asked the seller where it came from, and she said that her graphic design/marketing company had obtained it, along with some other materials, from Nintendo for a photo shoot. A quick search of her name on Google turned up her marketing firm's website, and sure enough, their client list included Nintendo of America. So while it's not an original piece, it's close enough, considering how little I paid for it