I have set up a gmail account and had it validated on my tour. I can see the calendar under that gmail account and can access it. The problem is that it won't automatically sync between my computer google calendar and my phone. What I type into my phone does not show up on my computer and vice versa. I know there is a way to do this b/c my friend has same phone and hers works. She does not remember what she did differently.
Try to go into options on your blackberry tour-->advanced options--->applications---->select "Google Sync" and change all setting to "allow" and save it. You can also view this information at the link provided below.