Companies that sell computers with GNU/Linux preinstalled
Minifree offers replacement of proprietary firmware with LibreBoot, a 100% free software BIOS, and sells laptops that bear the Respects Your Freedom certification mark. These ship preinstalled with LibreBoot and a fully free GNU/Linux distribution such as Trisquel, gNewSense or Parabola.
Los Alamos Computers (LAC) sells laptops, desktops and servers preinstalled with fully free GNU/Linux distributions, including gNewSense. In addition, they donate a portion of every sale of such systems to the FSF.
InaTux also offers computers preinstalled with gNewSense.
ThinkPenguin.com offers computers preinstalled with Trisquel.
You may check out and promote an idea about gNewSense being preinstalled on computers from Dell. (Note: requires you to have a Dell account!)