DWGs and DXFs are great, but what do you do when you need to import an image to use as a reference for a drawing? This video covers the ins and out of using image files as reference for architectural modeling.
http://sketchup.com/
http://forums.sketchup.com
https://facebook.com/sketchup
Tweets by SketchUp
https://instagram.com/sketchup_official/
source