I went to a presentation recently that compared several payment services and their fees/rates, and Paypal's is ok, but mainly great if you're selling in high dollar amounts, and that requires approval from Paypal's side. The best that I saw is a library called Stripe.js, but that requires some more technical know how in order to get it working.
You can definitely go a lot worse than Paypal though.
It isn't the simplest of things to set up a payment service in general though - the credit card industry regulates the transactions tightly.