Regarding creating a Community in Google+, I've never created one, so my questions are, how can my forthcoming Google+ Community be found with a url like this, for example: https://plus.google.com/+square Also, I assume only people with gmail can add something to my Google+ Community, is that correct? And lastly, if someone adds something to my Community, can they be messaged? If so, would it be by clicking on what they added, or do they have to show their gmail address to be contacted, or what?
It's totally up to the people if they want or do not want to be contacted. By default there's no contact information provided. The only way you can reach someone is you reply to their posts in hopes they'll see it. You'll receive notifications (upper right corner) from the people you follow if they happen to post new posts / comments on the G+ home page (not in your community). You do not really need any notifications from your G+ community page since you'll be able to see who posted what. You will be able to moderate your G+ community page (remove unwanted posts, approve posts that were automatically marked as spam). I have no clue how to make your link to show like plus.google.com/+square. Can this be done for a community page? Not sure. The standard community page link looks something like this: https://plus.google.com/communities/112906456891174626789 And yes your community page will be associated with your gmail address. You will be receiving notifications to your gmail address regarding new posts on the G+ home page as well.