-Often I think social media is one piece of a larger portfolio. So for example, a government agency may contract out a large part of their public affairs work. You could find who has these contracts and position yourself as a potential sub-contractor.
-Make sure to sign up for job openings as occasionally there are positions that open with these titles. USAJOBS is the best federal resource and I know there are a few state/local ones as well.
-Networking, thought leadership is still key.
-I still think social media in government is early. Despite all the talk and buzz, there are still a limited number of implemented gov 2.0 projects, social media positions, and social media contracts. But I think they are coming...