A pre-event information email will go out 2 to 3 days before the event with all the necessary information.
Also, check the events page for any information regarding the event. All currently available events are listed here: https://www.entryninja.com/events/event
Some events would normally have a link that takes you to their official website where you would be able to access more info on specific event or contact the event organizer directly
If you have already entered for the event in question, then you can simply checkup on the event on your dashboard: https://enter.entryninja.com/dashboard