To control the network settings with the command line try:

networksetup -listnetworkserviceorder

Then:

To display current state of wireless:

networksetup -getairportpower <device name>

Or to turn wireless off or on:

networksetup -setairportpower <device name> <on off>

For a longer description of these see:

http://reviews.cnet.com/8301-13727_7-57566448-263/how-to-adjust-network-settings-in-os-x-via-the-command-line/