SetFont(string family [, string style [, float size]])
define('FPDF_FONTPATH','/home/www/font/');
require('fpdf.php');
family
style
size
//Times normal 12
$pdf->SetFont('Times');
//Arial negreta 14
$pdf->SetFont('Arial','B',14);
//Suprimeix negreta
$pdf->SetFont('');
//Times negreta, cursiva i subratllada 14
$pdf->SetFont('Times','BIU');