on the home page at http://my.currentcost.com/account/home.php
there's a section down towards the bottom of the page, called "Devices". If you click the "+" (plus), it expands out and shows what devices you have registered there. Just under the serial number at the top of the section is a row of buttons - one of them should say "Register Google PowerMeter". When you click that, you get flicked over the Google Power Meter, you log in, answer a few questions, and it's set up.
I imagine you did all that? If so, what happens when you click the "Test Google PowerMeter" button (again on the currentcost home page) - it should say "Google test successful!" just under the Devices heading above the Device serial number. Clicking "Visit Google PowerMeter" takes you straight to google where you can see you graphs.. (if it's all working of course).