Most people, when using a table to lay out a page with sidebars, will do the obvious thing, like this (view the source of this page to see how I've constructed these tables):

The problem is that, in the HTML file, you must include the text for the sidebar before the main body text. This isn't what you want for search engines! You want the main body to go first. The trick is to do something like this:

Of course, you'll want to make that empty cell as small as possible, or even invisible. However, this puts the main body of text in the first row, ahead of the sidebar, which is in the second row. Use another column and a transparent gif to make a suitable margin, or use tables in each cell to set the margins:

You can even use this trick to put banner ads (shown below in red) above your main body, but after the main body text in the HTML file, using overlapping table cells and an invisible image (shown here in blue). Size the invisible image to just pass the banner ad (this only works right if the banner cell does not include regular text - it must include only GIFs - as text may vary in size depending on user preferences).

	<br> Main Body of Text goes here (use rowspan=3)
(use colspan=2)
Side Bar

• a transparent 1x1 GIF (please copy to your site, don't link to mine)