I use an iPhone app called HamSat. It seems to work pretty well. As with all programs like this, you need to carefully enter the coordinates of your location for the pass prediction data to be accurate. I believe that their may be some other apps for the iPhone which use the built-in GPS to get an accurate fix on your location.
I also use a program called MacDoppler on my Mac to generate satellite prediction lists. This program can also control you radio to compensate for Doppler shift and an az/el rotator to automatically track satellites.
Have fun with the Sats!
- Fred (AB1OC) President, Nashua Area Radio Society