Yeah, figure out a niche within the main market.
Hire some monkeys to post their asses off, particularly focusing on discussing current news within the market. You can get some for as low as 10c/post.
Run some contests. Give away Amazon gift cards or whatever applies to your market. You can even offer free advertising on the forum as prizes.
If you need more ideas, PM me. I have a ton which I won't post here.
