Here is another back-dated post to direct folks to the right spot. Stopdesign.com has a good article on using Google Calendar, and it links here referencing...
Add agenda to Gmail
This one is a little more involved, but useful if you’re primarily a Gmail user and don't keep Calendar running all the time. [read more]
The content that is being referenced here is available on TLW - Add Your Agenda To Your Gmail. Go check it out.