can i see how accurate my gps reading is?

Yes.  From the main screen, select Options (Right Soft Key) and then Preferences.  Select General.  Use the up and down Rocker Key to select Show GPS Accuracy.  Press Set (Left Soft Key) so that the box next to the option is checked.  Press OK to save the setting.  When viewing your GPS position on a map, an oval defines the margin of error of your GPS reading, so that your actual location should be within the oval on the map.