Hi Abby,
Thanks for your interest in our plugins! The default behavior for Event Tickets Plus is that an email is sent to the buyer when an order is completed. Any other automatic emails/notifications (such as to the admin or organizer) would depend on the settings/options of your ecommerce provider.
I suspect that WooCommerce at least has a way to send notifications when products are purchased, but it might require an extension. I recommend that you look into the capabilities of the available ecommerce providers and make your decision from there 🙂
Let us know if you have any further questions about ET+!
Cheers,
Leah