I think your question needs to be a bit clearer, because you're describing something that is visual.
Is this like a banner ad, or do you want the image as a background of what's on the left size?
If you the image is too big you have three choices, resize the image itself, resize the image in the img tag (
Or you can resize it in CSS as well - making
#foo { width:200px; height: 500px; }
Lastly you can also set an image to the background of a container in CSS, i don't know if that's what you mean, to do that is also easy, this would be your html:
some text maybe?
Your css:
#banner { background: ('banner.jpg') repeat; width:200px; height: 500px;}
That's an example, repeat can be interchanged for repeat-x, or repeat-y.
Hope that helps.