I cant remember who was looking for info on what to use for room boxes for gifts they were making for family but i found this: http://www.ebay.com/itm/Kits-DIY-Wood-Dollhouse-miniature-with-LED-Furniture-cover-Princess-room-/251929306788?hash=item3aa82826a4:g:zcYAAOSw7ThUmON1
I use to to all the dept stores around xmas and look at the resin ornaments. Found a couple of chairs and dogs and the like but you cant find them much anymore.
I've used both also. I have printed my own off DIY sites and purchased from dollhouse shops. I have also used scrapbook paper which is thinner than card stock, You can use plain scrapbook paper for your printing of said wallpaper too.