A WiFi iPad does not have GPS and therefore is only able to indirectly determine its location using the location of WiFi hotspots. If your iPad is near a WiFi hotspot whose location has been registered on the location database, then the iPad will be able to approximately determine where it is, but out of touch with WiFi it will have no location finding capability.
Only the 3G iPads have GPS, because some of the electronics needed for GPS and 3G are similar and are incorporated into the 'silicon chips' in the iPad.