Its been log i have done this but forgot to share with all visitors. This article will guide you on how to add magento products to google base. This works only for first time but if you wish to submit automatically then yes its possible.
Step 1: Magento Google Base Feed Account Configuration
go to System >> Configuration >> Google API >> Google Base.
Enter details of the account you wish to use to publish your products feed on. Select the default target country of your feed and select Yes in ‘Update Google Base Item when Product is updated’.
Step 2: Adding Required ‘condition’ Attribute To Magento
Go to Catalogue >> Attributes >> Manage Attributes and click Add New Attribute. Populate all fields with following values:
attribute code, scope, attribute type (dropdown), unique value no, etc
Then click on Manage Label / Options in top left. Type ‘condition’ in Admin and ‘Condition’ in all store views. Then click Add Option, type ‘new’ in all fields and add position ‘1’ and select ‘Is Default’.
Click on Add Option again and type ‘used’ in all fields and add position ‘2’ and click on save button.
Step 3: Now go to the particular attribute set and add condition attribute to ‘general’ group and save the attribute set.
Step 4: now lets populate the new attribute ‘condition’, go to Catalogue > Manage Products, select products you want to update, select Update attributes from the Actions drop down and confirm by clicking SUBMIT. On the next screen, find Condition, change it to new and confirm Save.
The list of required and recommended attributes for products can be found here: