Scan for mobile phones?
In the article you link "Bluetooth Enabled" means discoverable.

In discoverable mode, a Bluetooth device responds to inquiry messages with its name and unique ID. This is the feature of Bluetooth allowing it to be tracked.

My limited understanding of GSM/3G/EDGE is that devices can only be tracked by the operator or other holder of the network's encryption keys. If this is your intention, try http://crypto.stackexchange.com