Need help centering paypal button

[djjeffa]

here is what I have but it always goes to the left I want it where its at but in the center of the page could anyone help?

<!-- logo -->
<a name="top"></a>

  <tr>
    <th align="center" scope="row"><table width="100%"  border="0" cellpadding="0" cellspacing="0" background="xtreem/header_exp/backgroundd.jpg">
      <tr>
        <th width="80%" align="left" scope="row"><img src="xtreem/header_exp/left.jpg" width="253" height="92"></th>
        <td width="20%" align="right"><img src="xtreem/header_exp/right.gif" width="498" height="92"></td>
      </tr>


</table>
$spacer_open $_phpinclude_output
<map name="Map">
  <area shape="rect" coords="94,6,146,24" href="http://host74.ipowerweb.com/%7Earctic-r/adv_index.php">
  <area shape="rect" coords="169,5,258,24" href="http://host74.ipowerweb.com/%7Earctic-r/xtreem/">
  <area shape="rect" coords="281,6,373,26" href="http://host74.ipowerweb.com/%7Earctic-r/gallery/">
  <area shape="rect" coords="395,6,492,24" href="arcade.php">
  <area shape="rect" coords="4,71,53,87" href="index.php">
  <area shape="rect" coords="522,27,721,66" href="index.php">
</map>
<a href="http://djjeffa.com/vb/showthread.php?t=1760">
<img border="0" src="http://djjeffa.com/images/Donate.gif" width="62" height="31" align="center"></a>&nbsp;