Some internet search sites can be used to track information in social network sites. Delicious, OneRiot, StumbleUpon, Scoopler and Google Social Search (Google Labs) are recommended by Per and Susanne Koch in "Top 5 sites for social search." Pandia Search Engine News, 2 November, 2009.
Read the post to decide if these social search sites would help you retrieve more relevant results for your research.
For an in-depth explanation of Google Social Search read Danny Sullivan's post "Google Social Search Launches, Gives Results From Your Trusted 'Social Circle'." Search Engine Land, 26 Oct, 2009.