versuchs mal so:
for ( $i = 0 ; $i < $total_books ; $i++ ){
$zahler++;
if($zahler == 5){
$zaehlöre = 0;
print "</td></tr>\n<tr><td>";
}
$bk_ASIN1 = mysql_result($sql_booklist,$i,"ASIN");
$bk_pic1 = mysql_result($sql_booklist,$i,"pic");
print "<A HREF="http://www.amazon.de/exec/obidos/ASIN/$bk_ASIN1/accessomaniaf-21">\n";
print "<IMG SRC="$bk_pic1" border="0" alt="cover"></A> \n";
}