Edit (or find) a skin that has a pane where you want the header image, not a logo control.  Then you can insert any image you want in a module in that pane.  Or you can create a sepeart skin for each page and use the image as part of your skin.

Jeff

Another trick :) if you run into times when you need to change the "logo" often. Is to create a pane where the "logo/Image" is to go and put a banner module in then you can control the image via the banner group and settings. I did / do this over using an image in a text box cause it was easier to swap back and forth. It also allowed different images to be used per user visit. Not to mention there were never issues with someone hitting enter before the image insert etc. Just gave me more control over the image.

No way is right or wrong, just depends on the end results you want.