How to get rid of background

If I'm getting you correctly here: You already
cut out the picture of the dog, and you are
trying to put the dog into another image that
has a white backgound, Right?

Need to know if the image you are trying to
put the dog into is simply a plain white back
ground or is it a picture with a mostly white
background ?

I don't know what program your using? I use GIMP and I figure they are all fairly similar. When you remove the back ground form the image you will often see what ever the color is that you have selected in you color palette. It has something to do with the type of file, .jpg's for example. To keep this from happening add an Alpha Layer to the image. Then when you remove the background you will see a black and grey checkerboard box. This is what you see when there is no back ground to you image. Then to keep it this way save it as a .png or .gif file. It is good to use when you know you'll want to use the same image over and over like we do with Lootie.