I help run a small pressure group in my home town which aims to ensure the local authorities always look at a bigger picture. We have a website where we publish our research papers, opinions and articles. This was never likely to receive thousands of visitors each week; dozens was always going to be fine. But from the start, we did want to use online marketing to get the message out, and the website was always going to be an asset.
So we put up a ‘welcome mat’ (a full-page popup) which invited people to receive emailed updates about what we were up to. And it’s really worked. A couple of people signed up in the first week, then a couple more, and before we knew it, we had a mailing list of over 400. For a fully-requested email on a niche subject in a single locality, that’s amazing. Best of all, it’s cost nothing.
There really isn’t any reason why you can’t do this on your website. Lists like these take time to grow. But as I always say, even if you may not be around to see the results, your successors will thank you for starting things off.