Passmark WirelessMon is what you're looking for.
It has a 30-day evaluation trial and works perfectly on Windows 7.
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Using this software will display a list of every wireless network in the local area, providing a breakdown of its MAC address, channel, and other useful information.
For example, if there are six access points in range, all with an SSID, "hotel_ap", then you'll see six individual rows as separate entries.
You can then find one with the MAC address you want, right-click it, and select 'connect to AP'. The in-built windows wireless network manager will then drop whatever (if any) connection you currently have, and attempt to connect to the device with the MAC address you selected within the Passmark Wireless Monitor software.
You can also set the software to start with your computer, as well as build up a list of hotspot priorities, by MAC address. It's a pretty effective bit of kit for what you're after.
Hope this helps!
SOURCE: I'm using it to write this!