Create your own online community!
Encourage your clients to blog to your site. Now I know this could be dangerous if your customer service is not what it should be. But think about the advantages of networking with your center of influence and your hopefully happy clients, exchange home owner/home seller tips. Microsoft Office Live will allow you to set up a customer interaction area.
Remember your customers are most likely out there talking about you on other blog sites, how about giving them a place to talk with you and each other.
If creating your own online community is too daunting, jump in to as many discussion/forum groups in you area and post positive answers to industry questions. This is another way to brand you as a community expert. Participation will also allow you to understand what people are thinking about the market, the area and it turn allow you to help influence their impressions of the market.