you'll need to bring up the network, ie.,
ifconfig wlan0 up
you can also try:
iwlist wlan0 scan
to see which, if any, networks your wireless card can "see". The procedure doesn't stop after the modprobe step. Check the Wiki (do a Google for 'ndiswrapper' and it should be the first hit) and follow the instructions step for step and you should have no problems, especially after getting everything installed correctly.