VistaStumbler is really useful tool optimised for vista to connect to any wireless network with in the range of connectivity. It will let you discover all the information needed to correctly setup a private network, including BSSID, encryption, signal strength, channel and other information required.
It lets you setup and connect to any wireless network quickly and easily through its own easy to use interface.
VistaStumbler supports many of the wireless network cards and you can even get more information about your wireless card fitted in your machine. Stability and memory usage is improved to a great extent in the latest version of the program.
You can customize the scanning speed to search the wireless networks and it also allows you to play a sound when network is found.