If you want to learn more about using a background image, let me know. It's a very simple matter of CSS coding (cascading style sheets, which blogspot uses). In fact, here's the code, for specifying the <body> tag, that invoked the background image:
background-image: url(http://3.bp.blogspot.com/_o3nHqz3ofwI/RZcYAG81sHI/The URL is just what blogspot told me after I uploaded the background image (C49645B.gif) to a temporary post.
AAAAAAAAABI/KXgs97GAb5w/s320/C49645B.gif);
background-repeat: repeat;
