So you want you AutoCAD Layout to be black just like you model space background for whatever reason or preference you have? Simple to do and here is how to do it. I this video Autodesk Screencast you can see the command steps I use in real-time and hear my voice instead of just looking at images and and text explanation. The post I wrote back in 2007 & 2010 on this topic is one of the top ten read on this blog in over 10 years so apparently there is a common need.
2010 blog post tutorial: AutoCAD Layout Background Color to Solid Black or Other Color
Now the new Autodesk Screencast version!