To identify the satellites you see or photograph, go to CalSky, let it find your location (automatic), then under the topic headings, click Satellites and then the Geostationary link. You'll be shown a list of geosats, with their magnitudes and positions (in R.A. and Dec.), that are visible from your site that night.

You can easily find out by visiting one of these four popular web sites: Chris Peat's Heavens Above Science@NASA‘s J-Pass NASA's SkyWatch Spaceweather.com Each will ask for your zip code or city, and respond with a list of suggested spotting times.