I'm going to go through a basic tutorial here today on importing iCal addresses into your Drupal 7 site as nodes. While there are already several modules that allow you to show your google (or other) calendar data on your site, importing your calendar with those modules usually has a few restrictions, such as limiting the specific data you can show, and not having very good methods for customizing your style. Using Feeds to import the data as nodes allows you to bring an events calendar to your site that is 100% customizable by you, the same way any other nodes on your site are customized.