Ragazzi stavo leggendo la pillola presente sul forum e mi sono adoperato per adeguare il codice alle mie esigenze:
ho creato il file .class
codice:
class _makePager {

 var $limit;
 var $page;
 var $numPages;
 var $offset;
 var $sql;
 var $menu;

 function _makePager ( $limit ) {

  $this->limit = $limit;

 }

 function _getPagerData ( $numHits, $page ) {

  $numHits = (int) $numHits;
  $this->limit = max((int) $this->limit, 1);
  $this->page = (int) $page;
  $this->numPages = ceil($numHits / $this->limit);
  $this->page = max($this->page, 1);
  $this->page = min($this->page, $this->numPages);
  $this->offset = ($this->page - 1) * $this->limit;
  $this->sql = " LIMIT ".$this->offset.", ".$this->limit;
  $this->_makeMenu();

 }

 function _makeMenu () {

  if ($this->numPages>1) {

   if ($this->page>1) $this->menu['PREVIOUS'] = ($this->page-1);

   for ($i=1; $i<=$this->numPages; $i++) {
    if ($i == $this->page) $this->menu['PAGES'][] = array (
                               'ID'     => $i,
                               'STATUS' => false
                              );
    else $this->menu['PAGES'][] = array (
                     'ID'     => $i,
                     'STATUS' => true
                    );
   }

   if ($this->page<$this->numPages) $this->menu['NEXT'] = ($this->page+1);

  }

 }

 function _getUri ( $_pagevar ) {

  $_getvars = $_SERVER["QUERY_STRING"];
  $_url = $_SERVER["PHP_SELF"]."?";
  $_getvars = explode( "&", $_getvars );

  for ($i=0; $i!=count($_getvars); $i++) {
   list ($key, $value) = explode( "=", $_getvars[$i] );
   if (($key)&&($value)) if ($key!=$_pagevar) $_url.= "{$key}={$value}&";
  }

  return "{$_url}{$_pagevar}=";

 }

}
e poi nella pagina che estrae i risultati ho messo:
Codice PHP:
<?
require_once("php.sql.pager.class");
$_PAGER = new _makePager(2);

include("top_foot.inc.php");
include("config.inc.php");
top();
$db = mysql_connect($db_host, $db_user, $db_password);
$_sql = mysql_query("SELECT COUNT(*) FROM prodotti");
$_PAGER =  _getPagerData(mysql_result($_sql),$_GET[p]);

$_sql = mysql_query("SELECT * FROM prodotti ORDER BY marca {$_PAGER->sql}");
while ($row = mysql_fetch_row($_sql)) {
 // STAMPO I RISULTATI
echo "$row[marca]";
}
if ($_PAGER->menu['PREVIOUS']) echo "<a href=\"".$_PAGER->_getUri("p").$_PAGER->menu['PREVIOUS']."\">pagina precedente</a>";

$_PGS = $_PAGER->menu['PAGES'];
for ($j=0; $j!=count($_PGS); $j++) {

 if ($_PGS[$j]['STATUS']) echo " [ <a href=\"".$_PAGER->_getUri("p").$_PGS[$j]['ID']."\">{$_PGS[$j]['ID']}</a> ] ";
 else echo $_PGS[$j]['ID'];

}

if ($_PAGER->menu['NEXT']) echo "<a href=\"".$_PAGER->_getUri("p").$_PAGER->menu['NEXT']."\">pagina successiva</a>";

mysql_close($db); 
                                    foot();
                                    ?>
Se testo questa pagine esce l'errore: Call to undefined function: _getpagerdata()

WHy?