ojalá me puedan ayudar:
Código PHP:
function Text2url($string) {
$spacer = "-";
$string = trim($string);
$string = strtolower($string);
$string = trim(ereg_replace("[^ A-Za-z0-9_]", " ", $string));
$string = ereg_replace("[ \t\n\r]+", "-", $string);
$string = str_replace(" ", $spacer, $string);
$string = ereg_replace("[ -]+", "-", $string);
return $string;
}