Payment options are added to website using payment gateways. Each of them will have their of features and commission rate. Take a quick at the most popular gateways. Below is also the link in wikihow on integrating payment gateway to the site
http://www.wikihow.com/Integrate-a-Payment-Gateway-Into-a-Website
Enets – www.enets.com
AsiaPay – www.asiapay.com
GT Payment – www.gtpayment.com
Paypal - www.paypal.com
WorldPay – www.worldpay.com
2Checkout – www.2checkout.com
Globalcollect – www.globalcollect.com