This question has been asked a few times in the past. A long time ago in the past, in fact. I'm not aware of any changes that would make this possible without too much complexity. But, I am wondering if anyone has come up with any working ideas.
What I am looking to do is to match the email address of an incoming email to someone in my contacts list. Tasker works with phone numbers in contacts, but I don't see anything about email addresses. AutoContacts seems to have the same limitation. I would imaging that the new SQL interface within Tasker might be able to solve this problem, but I am not a SQL expert. I am more interested in finding a solution that uses native Tasker or a plugin that can do this.
My intention is to trigger a specific action, not necessarily a notification, if an email is received from someone in my contacts list. I use AquaMail, so I am able to easily get the email address of the sender. I just need a way to match against my contacts and return a simple true or false so I can take my action.