If you're looking for your event's URL to share or promote your event you can find it in a few places.
If you've published your event but have not sold any tickets yet you can find it by going to the Events tab and clicking on the name of the event you're looking for the URL for. Then you can find the URL on the Event Home underneath the sample Buy Tickets button.
If you've already sold tickets to your event or if it's still a draft event, you copy the full URL by going to the live webpage. To do this go to the Events tab and click on the name of the event you're looking for the URL for. Then, from the Event Home click on the View Event option on the right hand side. Once the webpage opens up just copy the URL from your address bar.