Many organisations think that this means spam, this is not true. Email is one of the most under utilised legitimate tools for customer contact. If you already have customers then you can ask their permission to send them relevant information. If you want to spread your net wider you can purchase "opt in" email lists from reputable sources that are an excellent place to dip your toe in the water.
There are some magic rules when marketing by email and we would be delighted to help you set up a campaign, either stand alone or as part of another marketing drive. You can see the results instantly and measure your success or failure accurately.
Once you have dipped your toe in the water your want to immerse yourself in this new and effective medium. But beware, if it's done badly it will have a massive detrimental effect on your business.