name="iframe"
width="600"
height="650"
src="page0.html"
frameborder="0"
scrolling="auto" >
</iframe>
That creates the iframe and displays the zero page. Then I create the links to the other pages like this:
<li><a href="page1.html" target = "iframe">first page</a></li>
<li><a href="page2.html" target = "iframe">second page</a></li>
</ul>
You can add as many links as you need. Where I have the text "first page" you can place an image button or other text as suits your need.
I use this code on my web site.
Let us know if this works for you.