Actually paypal dosn't even require it.
But to get google checkout you need to setup an ssl on your hosting account.
Most hosting companies will charge for a shared SSL. But today I was doing some heavy research into what the customer acutally sees and everything you read on the net tells you that you need the "New High Assureance Certificate for SSL".
However when using Google Checkout or Paypal IDN the customer is taken off your site completely to their payment gateway and would never see the SSL part of your site.
So there's no need to spend hundreds of dollars unless you're going to be using a gateway payment system that keeps the customer on your site to make the payment.



