I am planning on setting up credit card payments on my site through Google Checkout. I was going to use the regular Notification API similar to PayPal's IPN, but I then found out about their Polling API and it has some compelling advantages that I could take advantage of. However, I am a little short on time and there seems to be a lot of documentation about this. Does anyone have or can find any basic sample code for this implementation (not integrated with a shopping cart or anything like that, just a buy now type thing). Also, I have already seen the sample code in Google Code and it doesn't clear much up.