Adding a CMS Static Block to your XML file. xml layout files are located under app/design/default/<your-theme>/layout/

layout.xml

<cms_index_index>
  <reference name="content">
      <block type="cms/block" name="static_block_name" before="-">
            <action method="setBlockId"><block_id>static_block_name</block_id></action>
      </block>
  </reference>
</cms_index_index>

notes:
<cms_index_index> tells it to only show up on the front page
before="-" tells it to show before all the other blocks on that page (at the top). To put it at the bottom, change it to after="-"