If the project is worthy enough, you should maintain full and complete control over the forum, until such time it becomes to much for one person to moderate. All the while, you keep an eye on members to spot the ones you think would do your site justice, and moderate it fairly, passionately, and professionally. Once you contact them about helping out, and they accept the position - you immediately make an announcement on your forum telling the members of the new moderator, and welcoming that new moderator so that they feel honored and cherished (something like that anyway).
That's a brief rundown of how it should/could go for your moderator search. You can find a complete run down by browsing a site known as Sitepoint.com.
As for promoting the site... you should be the one to do this, unless your willing to pay someone to help you get ranked in the SE's. Even if you pay someone for that service, don't expect to much to happen for the first 2-4 months (or longer, depending on the service).