What kind of texture are you trying to create? You can use images as textures and I often use PSP for this process. In the materials lab load a material in the diffuse column then choose the "P" to load the little man image, click on the pink button above the "P" (and the image) its the texture source editor click on a block or on load to import your image. Then you have an alpha channel here as well but that is another story... Cheers