I know this is an old post, but in case someone needs this.
You can start off by adding the direction “right to left” directive in the html tags using dir="rtl"
like the following:
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="<?php echo $this->getLang() ?>” lang="<?php echo $this->getLang() ?>” dir="rtl">
You can edit this in the files app/design/frontend/default/your_theme/template/page/3column.phtml
and the other files you use in this directory (2column-right.phtml , 2column-left.phtml)
This should make the direction of all your text from right to left.