You can set the normal table style to have the whole table align to the bottom. You should be able to do this by inserting a table, then Displaying the Styles and Formatting Task Pane. It should tell you which table style you have selected. Move over the name of the Style (it's Table Grid in 2003), and a drop-down arrow will appear. Choose modify from the drop-down list. Than, you can format the whole table by choosing Format|Table Properties (from the dialogue box). Move to the Cell tab and set the alignment to the bottom
You couls also make a table style from scratch
You can make sure it's the default style by finding it in the list part of the Styles and Formatting Task Pane and clicking on it's drop-down arrow. Then, you can set it as the default
tj