Tommy,
Before you go spending money on diffusors, please try what I've done in my 10'x12.5' room.
Get six 2'x4'x4" absorption panels, place two behind you and place two on the side walls at the first and second reflection points.
Then get a larger rug for the floor between the speakers and you for the first reflection points on the floor.
Then assess whether or not you need some diffusion on the wall behind your speakers.
You might be as surprised as I was after I ended up with this arrangement. When you look at my system pictures, don't pay any attention to the two smaller 2'x3'x2" panels behind my speakers on the side walls. They don't do anything and are going to be removed.
One thing about diffusion. Ethan Winer states in his new book that if diffusion is needed and used on the walls, they usually should be vertical diffusors. Three-D diffusion sends sound waves to the ceiling and floor besides vertically, and sometimes adds to the reflection problem. Three-D diffusion is best, if it's needed, on the ceiling since it scatters everywhere.
Chuck