Try this site, Don't know if they have Star Wars on there,
but maybe you can get some ideas for his room.

Here is a link that might be useful: Maries Manor

It all depends on how you want the room to look. If you are willing to use the border, I'd paint the top half of the room a blue or some color that is in the border and the bottom half a navy blue or other darker coordinating color. I would use posters to add the Star Wars theme. You could use Star Wars bedding and curtains or you could use a darker solid color. If you want more outer space stuff on the walls, you could add wallies or something that would require wallpapering an entire wall.

Here's another neat idea you could use, but it isn't directly Star Wars. http://www.wallies.com/pages/outer_space/1034.php

Here is a link that might be useful: Wallies

I have seen glow-in-the-dark paint to make a night sky in a kids room on TV. The paint is pale yellow during the day, and glows when the lights are out. Maybe you could outline the wallies, or part of the border and add some stars with simple dots on other parts of the wall. On the program they also did some splatter paint areas to make "galaxies" and painted in some meteors, too.

Also check places like the Discovery Store for planet or space related items.

Look in the children's section for coloring books etc. That will give you ideas on how the room could be set up. Also check your library for books in the children's section/or space section.