Here is a quick guide lines on connecting to google product search.
In your ezimerchant control panel go to 'Connect'
Scroll down the Connect page and look for 'Google product search' and hit connect
After hitting the 'connect' button it will ezimerchant will request access to your Google account, just hit grant access
Once you've granted ezimerchant access a google shopping feed will shop up in 'Sites & domains' for you to publish your products to
Then your done.