a navigation bar
Can you tell how it is done? Try to imagine, before reading on. You need to use a lot of attributes to harness this one. The table border is off, the cell spacing and padding are set to zero. The top row needs to span three colums, as does the bottom. The left and right rims span five rows. Examine the source of this page to see the html used (right-click, view source). But don't get lost!
snake in the grass
There is still a snake in the grass to be caught. Some browsers have the nasty trait of adding space around an image in a table cell. When you code your html neatly, each tag on a line, there is a "hard line break" between two tags. This break is often displayed as a "space" character.
To prevent this from happening both the TD tags need to be directly next to the image, without a line break or a space. This will make your code less attractive, less readable. But at least your page will look the way you set out to do. Have a look at the two sets of blue-orange squares. The html used is exactly the same, apart from the line breaks.