A ringworld, as in a strcutre 1 million miles across and the orbit of the earth in diameter? Do you know how fucking long that would take to walk around? Louis Wu only walked on about a 128th of the whole ring, and it spanned, what, 6 books. I have met Niven before in person, and he says that the novels will continue, so it will soon fill 7.
The ringworld is so fucking huge, here are some nerd stats i gleaned from Niven:
Mass: 2x10exp30 grams
Radius: .95x10exp8 miles
Circumference: 6x10exp8 miles
Width: .997x10exp6 miles
Surface area: 6x10exp14 square miles= 3 million times the area of the earth.
Even if most of the map were made up of nonaccessable area, the map file would be huge, and it would require a shitload of teleporters for the service stacks.