I often recommend to clients that they consider adding more articles to their site via a blog. The idea is to have an easy system to add content that is useful for both potential customers and search engines. If you are a plumber the content doesn’t necessarily have to be about how to fix a leaky pipe (although that couldn’t hurt). It might make sense for a plumber to write about how to plan for a kitchen remodel with the idea that the reader will eventually need a plumber.
This post Tipping & Gratuity Guidelines for International Travel on this discount airport parking site is a great example of how to use a blog post to get customers and links. They are targeting international travelers who are going to need long-term airport parking and providing them with info that I am sure a lot of them are looking for shortly before they travel. Once they get the customer to the blog they have a better chance of getting them to try the service. The only thing I would add perhaps is an offer to try a bit harder to get the reader to become a buyer.