Brown is a neutral...you can do whatever you want! I never thought I was any good at decorating until I realized that the same rules I applied to fashion can cross over into decorating.
We have a brown couch and are using light greens, bright greens and a slight pop of purple in our current redecorating. I also have one room that uses steel blue and white with brown. If your sofa is a dark brown, I would only avoid adding more dark colors, and keep things bright and light around the sofa.
For some reason the image won't work so here's the link:
The Elegant Abode | Flickr - Photo Sharing!
I love the light almost periwinkle walls, white and light metallic accents and one pop of purple color in this room.