Other Software Options

In addition to using the wireless-client, stumbling, and
network analysis software mentioned here, you have some
additional ways to search for wireless devices that don’t
belong ie some basic port-scanning and vulnerability
assessment tools can give you useful results.
Here is a quick list:

1 SuperScan
2 GFI LANguard
3 Nessus
4 NeWT
5 QualysGuard

These programs aren’t wireless specific but they may
be able to turn up wireless-device IP addresses and
other vulnerabilities that you wouldn’thave been able
to discover otherwise.