As the owner of a domain that matches with an ISP in Washington state (except for a missing "M" in mine), I feel Gail's pain. I send back a canned response to

As the owner of a domain that matches with an ISP in Washington state (except for a missing "M" in mine), I feel Gail's pain. I send back a canned response to most people once, then blacklist/drop the incoming address. The worst I had was when someone decided that I was the one doing the wrong thing and demanded that I forward the email to the correct person. I engaged them back and forth for a bit, then eventually found the contact details of the company, forwarding the email chain to them and pointing out their customer service person's stupidity. I got a nice reply from the CEO thanking me and an apology email from the CS person.