hm, really good tips
As for me,
1. participating in forums is very important, where you can add your link to your signature. But again not spamming, only useful and helpful posts. In this case, members will respect you and trust your site.
2. Exchange articles with related sites(but I don't do that, because too busy to write articles for someone else
), it's almost the same as posting at EZineArticles.
3. Create a facebook application and promote it
(It's not very easy, but the GPWA.org developed its first application (Places I've played) for Facebook users)
