Now that I am off of credit/debit cards I tend to e-mail a website that I would have used to purchase their services before I move on to find a way to pay with Bitcoin. Some have said that they have received inquiries in the past from others.
My contact is usually something along the lines of:
"Hello, I have dropped my credit/debit cards and have started using Bitcoin for all of my purchases. I wanted to use your service but notice that you have no option to pay with Bitcoin. Is this something you may be considering or have plans for implementing?"
Something simple like that. Takes a few seconds.
Let's create a list of links to various merchant's contact links so we can contact them and let them know that there are people out there that would like to pay with bitcoins on their websites.
I just sent one to Amazon. You can contact them by logging into your account, click Help, click on any of the Recommended topics on the bottom right. The page will have a "Contact Us" button.
Click "Prime or Something Else"
Choose one of the drop downs in section "2". Choose your method of contact (e-mail). Send your message.
Amazon's response:
Hello,
I'm sorry; currently we don't accept Bitcoin as a payment method on our website at this point.
However, I've forwarded your e-mail to our billing department for future construction.