Get a domain name and use that for your email; most providers let you set a catch-all that delivers everything to one place. So if you got, say, strawberrypigtails.egg you could give every service you sign up for a different address: ebay@strawberrypigtails.egg, sdf.org@strawberrypigtails.egg, pornhub@strawberrypigtails.egg and so on. Then, when you start getting loads of spam, you can look at where the email was sent to rather that where it came from and either take action against that service or just block emails sent to that address.