The October 2011 issue of Sky & Telescope contains an article entitled "Observing Geosynchronous Satellites," by Randy Rhea. It describes how easy and enjoyable it is to observe these high-flying satellites through a telescope. But it's very helpful if you can predict where to find these satellites and/or identify them after you've spotted them. This is best done with the aid of a few websites, listed below.
www.satobs.org includes a guide to "Observing Geostationary Satellites" that includes links to other resources.
www.satsig.net includes a "List of Satellites in Geostationary Orbit" with over 400 entries.
celestrak.com has orbital data (NORAD two-line elements) for 405 geosynchronous communications satellites. This data can be imported by most planetarium software to display the position of satellites.