Gift vouchers can be bought like regular articles. After you bought a gift voucher and the payment is received the voucher will be available for download as a pdf-file. You will find the download in the order overview in the "Your Account" section. So you can directly print out the voucher by yourself. If you prefer a printed version you can order the voucher along with other goods.
Gift Vouchers with a value from 20 to 100 EUR can be purchased here