Welcome to MobileRead, jhack!
Take a look at the Kindle store in the Amazon website. I know the Sony store sells individual issues of newspapers and magazines, along with subscriptions (often free for the first month) so I'm guessing Amazon does too. I used to get the San Jose Mercury News every day on my Sony PRS-900. It was pretty nifty!

I only stopped because it was too much for me to read and the issues piled up, unread.