This might seem a really small thing to you, but believe me, small things can become big things very quickly. If you put a good review of DG or DC on RPG.net, it might encourage someone who has never considered Dark Conspiracy before to have a look to see what you were so excited about. If they like what they see, then they might buy the books. Each book sale makes the likelihood of DC continuing that little bit more certain. The more books that get sold, the more people will want something new to run, the more people they will attract to DG and the cycle goes on again.
Word of mouth is by far and away the best and most effective form of advertising there is.
Miles from anywhere is a small town called Wall. In Wall there is a drugstore called Wall Drug. I would love to see people getting THIS excited about Dark Conspiracy. The more people get passionate about their game, the bigger it will get. The more pleasure and good stuff that people link with DC in their minds, the more they are going to want to get in on it.