1.) Start a blog where you write informative, engaging posts about tax problems. Use the blog to give your knowledge away, and in doing so, position yourselves as experts.
2.) Look for other blogs related to yours, subscribe to their feeds, and after a couple weeks of getting to know each blog, begin to join the discussions by adding your own comments (without spamming).
3.) Use Yahoo Answers to reply to tax-related questions from other users, again positioning yourself as an expert.
4.) Look for tax-related discussion groups on Yahoo Groups and Google Groups. Join the discussions, again without spamming.
That should get you started, and perhaps others can add more suggestions beyond the 4 above....