Simply add more columns to your table by outputting three data items at a time either using a counter in your loop or manually grabbing more data from the mysql result by adding extra $row = mysql_fetch_object() lines each time you want to populate a cell. Example:
printf("<table border=0 cellpadding=2 cellspacing=6
BGCOLOR=\"#ffeeee\">\n");
while (($row = mysql_fetch_object($result))){
printf("<tr>");
printf ("<td valign=\"top\"> sans-serif\" SIZE=\"-1\">%s <br>%s, %s <br>%s, %s %s <br>%s <br>%s
<br></td>\n",
$row->store, $row->address, $row->address2, $row->city, $row->state,
$row->zip, $row->country, $row->phone);
$row = mysql_fetch_object ($result);
if ($row)
printf ("<td valign=\"top\"> sans-serif\" SIZE=\"-1\">%s <br>%s, %s <br>%s, %s %s <br>%s <br>%s
<br></td>\n",
$row->store, $row->address, $row->address2, $row->city, $row->state,
$row->zip, $row->country, $row->phone);
else
echo "<td> </td>";
$row = mysql_fetch_object ($result);
if ($row)
printf ("<td valign=\"top\"> sans-serif\" SIZE=\"-1\">%s <br>%s, %s <br>%s, %s %s <br>%s <br>%s
<br></td>\n",
$row->store, $row->address, $row->address2, $row->city, $row->state,
$row->zip, $row->country, $row->phone);
else
echo "<td> </td>";
echo "</tr>";
}
printf("</table>\n");