- Everyday, when you get junk mail (physical, not email), Google the company website.
- When you get on the website look for a button that says "Contact Us" - this is usually at the top or bottom banner. Sometimes it is under "About Us" or "Customer Service"
- Look for a general contact email address. Many of them are info@(companyname).com.
- Send the company an email with the header: "Please remove from mailing list". In the body of the email type that again, followed by your name and address (exactly how it appears on the mail).
This method works very well - junk mail and at work has been reduced drastically.
There are of course services like Tonic (used to be Green Dimes) that will reduce your junk mail for a few (or sometimes free), but they are guaranteed for all mail. If you keep on top of your junk mail on a daily, or even weekly basis, companies will literally get the message.