I'm about to go, so I don't have much time to fully explain what I'm about to say ...
You can use sockets to "do stuff" on a webpage as soon as a player connects to your server. Once on that webpage, you can "do stuff" that makes the site's server send you an email.
So AMXX connects to a website, and a website sends you an email. That's one way you may be able to do it. I'd help you out if I weren't too busy. Maybe someone who's more familiar with sockets can be more specific.
Ok, gotta run!
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