All our models are delivered as STL Files and are designed to be printed on a 3D Printer. Home 3D printers start about $300US.
I would go for a printer that has at least a 150 x 150 x 150 build volume and uses PLA filament
The best value for money printer at the moment is the Prusa i3 MK2 http://shop.prusa3d.com/en/3d-printers/59-original-prusa-i3-mk2-kit.html
Then you will need Filament, which is the plastic that the printer uses to make the models, It's about $25 per kilo
Once you have that, its a simple matter of downloading the files from our website and them printing them. Your printer will come with software that will allow you to scale the models and set the quality of the print before printing.
Our Help section on our site also has more information http://www.printablescenery.com/knowledgebase