Best method:

background: #color url(../images/foo.jpg) top/center right/left repeat-x/y etc..) Additionally you can use px values to place the image too. e.g. for say a single image rollover effect.

#foo a {
background: #color url(../images/foo.jpg) 0px 0px no-repeat)
}

#foo a:hover {
background: #color url(../images/foo.jpg) 0px -50px no-repeat)
}