The Illinois Historic Preservation Agency has a great collection of paper models of historic Illinois buildings. You can put together a very nice early 20th century mid-western town from these models.
Paper Models
Paper Models For Dropships, Shuttlecraft, Science Fiction Tank, Warehouses
Genet Models offers some free paper models for Dropships, Shuttlecraft, a Science Fiction Tank that looks like it is from the movie Aliens, and some science fiction style warehouses.
Toyota Landcruiser Paper Model
For your modern skirmsih games — perhaps as a “Technical” — here’s a paper model of a Toyota Landcruiser. It’s too large as currently construed, but since its in GIF format, it would be very easy to resize.
Post-Apocalypse Armored and Armed Winnebago
Squirmydad has a paper model of a post-apocalypse armed and armored Winnebago.