Filed a trademark, now what?

I started a subreddit that got big with the intention to start a website around it. I knew it'd be popular, so of course there were/are competitors, which is why I filed a trademark. The mark has been approved, and now I'm wondering what my next step would be. I'd like to contact an internet/trademark lawyer to go after the competitors, but I am not sure what this would cost, or where I'd even start looking. Suggestions?