Using Frames

This page explains how to incorporate a guestbook created with Spam Free Guestbook Service into your site using html frames

Indeed you can simply place a link to the guestbook from your site, but if you wish to make it really look like the guestbook is a part of your site, you can do the following:

<HTML>
<HEAD>
<TITLE>A simple frameset document</TITLE>
</HEAD>
<FRAMESET cols="25%, 75%">
<FRAME src="http://www.yourdomain.com/your_menu.html">
<FRAME src="http://www.sf-gb.com/your_guestbook/index.html">
</FRAMESET>
</HTML>

*Note that there is no BODY tag in this case.

If you save this as a page guestbook.html on your domain, opening URL http://www.yourdomain.com/guestbook.html will produce something like this:
Your
Menu
Guestbook

I.e. it will look like a guestbook is a part of your site and users will not even notice that it opens from a different domain.

If you like it horizontal style, you can use the following instead:

<HTML>
<HEAD>
<TITLE>A simple frameset document</TITLE>
</HEAD>
<FRAMESET rows="20%, 80%">
<FRAME src="http://www.yourdomain.com/your_menu.html">
<FRAME src="http://www.sf-gb.com/your_guestbook/index.html">
</FRAMESET>
</HTML>

This will produce something like this:
Your Menu
Guestbook

If you wish to know more about frames - you can read, for example, this page.