Depends on where you want the buttons to appear. Take a close look at inc_top.asp - that is the page that contains the headings. If you want the buttons on the top, one option is to carefully alter that page.
The easiest way would be to pick a select few of existing graphics, make notes of the file names and create replacement graphics with the same file names. When you feel more comfortable with the code you can start replacing the text links with graphics. When working with the code the 'search' and 'replace' features become your best friend. Later Simonduz