When you click add URL in a search engine, or a traditional directory, you want to be specific. How can you stand out from a big crowd? You have to have something that nobody else has. And once you have it, you make sure people find it. A directory may put your web site several pages away from the first page, making it unlikely that surfers will ever see it. So use specific keywords and categories, like “dungeon master tutorials for X campaign” rather than “Dungeons and Dragons site.” Then people looking for that specific information will be drawn to you.