I have been trying and trying to make a background like you see in the commercials that are just white, but have some depth to them and maybe like a ramp of grey on the corners and you can see a cress between what looks like the ground and the wall. I was wondering if some one could give a tutorail on how to make this effect.
I just want it to be a 2D layer and not any 3D elements.
Well the easiest way to do this is to create a white background and add a little vignette. Maybe add also some grain so it stays in sync with your keyed foreground element.
The best way I've seen is to make it a 3D layer and then add a new Point Light and place it in front of it. Move it away on the Z axis to make the edges of the layer darker like a vignette. If you don't want it to be 3D, perhaps you could pre-compose this layer and have it 3D in there, but not in your main comp. You have a lot of power adjusting it this way.
If you want to make the vignette with no 3D at all, make a new solid the same size as your comp. Make it black and stack it directly over your white layer. With your new black layer selected, double click the round mask button at the top. This will make a round eliptical mask the same size as your comp. In the timeline, check "invert" beside the mask so that the black is now showing around the edges. In the same area set the Feather property to soften it up. If you add a subtle texture to your white layer, you might want to try to set the blend mode of the black layer to multiply.
Sorry, some of my facts may be off. I'm used to just doing it and not writing about it without it in front of me.