Welcome to Trulia.
I am assuming that you are selling your house on your own (FSBO). There are many websites that specialize in advertizing FSBOs.
As per your question, I am also assuming that you are not a web marketing veteran so starting with websites such as http://www.forsalebyowner.com , http://www.owners.com might be easier that advertizing through Blogging and other online media that require more technical understanding (SEO) to be really effective.
Something also you may want to contemplate is MLS only providers as to increase your exposure to local real estate agents.