All the groups that you belong to are listed on your personal My groups page. If you manage or own a group, that’s indicated next to the name of the group.
Do you get too much email for a particular group? You can opt to get a summary of messages sent to a group once a day instead of receiving each message separately. Or, perhaps you'd prefer to just read messages in the group's discussion archive (forum page) instead of receiving messages in your inbox.
It's easy to change your email preferences, and even to unsubscribe from a group altogether.
Go to your My groups page.
Select an email subscription option.
Click to unsubscribe.