> I was thinking along this line as well. Of course you might want to think about the scale issues.
>
> In Disneyland the rails have a gauge of 36" and the locomotives are scaled down to be proportional to this. This is where the notion of "everything" being 5/8 scale. Of course, having Art Linklater mention this prominently in the opening day TV show furthered this legend. In truth many scales are used to create the correct sense of proportion and techniques of forced perspective are used in many places in the park.
>

36" is Narrow Gauge. The locomotives at Disneyland were/are not scaled down. They're actual narrow gauge locomotives.

G Scale is loosely based off of narrow gauge trackage, although there have been a lot of variations on it. Many manufacturers produce standard guage equipment for it, which creates a lot of mis-scaled rolling stock and locomotives for G scale.

LGB produced a model of Ward Kimball's Chloe and some sightseeing cars for it about fifteen years ago. They're yough to find now.

As for structures, as long as you stick to the G scale proportions, you should be fine. Companys such as Plastruct and Evergreen make items for scratchbuilding. You could work off of the scaled paper models as templates to use for cutting styrene.