Getting good interface controls

I have noticed my attempts to make a good interface on the ipad the images have come out blurry, stretched and not looking good.

How do you get a good clear interface for something like a controller?

By correctly sizing it through code.
You must design for the sizes and aspect ratio, iPad is 4:3 while the iphones and itouch are 3:2 aspect ratio for example, that already leads to blur.

I have done this, it looks like heavy anti aliasing or something.

I think it is more to do with the file type or me not knowing what is the best way to get something on.

The project worked perfectly on 1024/768 standalone but in the ipad the 3D parts look great but the couple of places with GUI overlays look crap.