Notifications can be sent per the schedule you setup, but are not generated when a change is made to an event. You can however set up a digest email that goes out to a distribution list and this could be emailed out whenever there is a change or update to one or more events.
Reminders can be set for email and your phone.
Regarding how to set up a calendar so you can see another users events. I'll step through the method that I think will allow you to accomplish what you want to do.
1. You (User 1) would share your calendar another user (user 2) granting them "Can add, delete, and change events" rights. This can be done using the calendar's dropdown menu (the small arrow next to the calendar name) or the Share button when the calendar you want to share is the calendar you are currently viewing. Both perform the same action.
2. Important Note: you (User 1) must grant User 2 "Can add, delete, and change events" rights.
3. User 2 will now see your calendar in his/her list of calendars under their "Shared with you" calendar list on the left side when they sign in.
4. User 2 would then add an event to his/her calendar. This brings up the EVENT INFORMATION dialog. User 2 can then select the "checkbox" for your calendar among the calendars listed on the right side of the EVENT INFORMATION dialog in the "ALSO SHOWS ON" section.
5. Both users will then be able to see the event on "Your" calendar.
6. You can repeat the process for other users so that each user can create events that will show up on your calendar.
7. Note that when you share in this manner, all users can "Can add, delete, and change events". So they need to be aware that if they delete or change an event on your shared calendar, the event will go away or change for all users that have the right to edit your "shared" calendar.
8. You can share any calendar that you have created...so if you want to keep a private personal calendar, I would recommend creating a calendar that you want to share, and not sharing your own "Main" calendar. It just depends on the exact use you have for your "Main" calendar.
9. An additional feature...you could then "Publish" the calendar your have shared so anyone can view the calendar on line. You can also publish the shared calendar with a password restriction if you want to control who can view the calendar on line by sending them the URL. A password protected calendar won't show up in the "Public" list of calendars you can browse through.
10. Another way to get everyone's events to be merged into one view is to use the mix-in features. This kind of superimposes an entire calendar onto another. If you used the mix-ins, when you create an event, you would not use the Also Show On setting.
Neither way is better than the other; it just depends your situation and desired workflow.
