I was setting up multiple wireless access points with the same security and the same SSID. I had no way in windows to tell which AP I was connecting to. I needed to know because as I moved through the office I needed to ensure the computer was jumping onto the AP with the strongest signal in that area. One of my IT staff found a great tool that would tell me this information. This tool is called inSSIDer 2. We loaded inSSIDer 2 then walked around with a laptop and sure enough the tool highlighted the AP we were connected to. This gave me confirmation that the setup worked as planned. inSSIDER 2 is an alternative to Netstumbler and works well on Windows Vista and Windows 7. It can be used for much more then what I used it for. Here is a list of uses from the makers website:
You can download the tool here: http://www.metageek.net/products/inssider/
Another good tool when working with Wireless networks is Wifi Analyzer. This for an Android phone and is free.
You can learn more about this tool here: https://market.android.com/details?id=com.farproc.wifi.analyzer