You can connect to the Emulator via Telnet. You then have a Emulator console that lets you enter certain data like geo fixes, network etc.
How to use the console is extensively explained here. To connect to the console open a command line and type
telnet localhost 5554
You then can use the geo command to set a latitude, longitude and if needed altitude on the device that is passed to all programs using the gps location provider. See the link above for further instructions.
The specific command to run in the console is
geo fix <longitude value> <latitude value>
I found this site useful for finding a realistic lat/lng: http://itouchmap.com/latlong.html
If you need more then one coordinate you can use a kml file with a route as well it is a little bit described in this article. I can't find a better source at the moment.