I use the Netgear WDNA 3100A, it's kind of a hassle to install, it is supposed to download the installer from Netgear but that does not always work. Yah, it's a good cheap solution and if you buy it new you'll get an install disk, use the windows 7 drivers and then update them using Windows Update. Netgear has the drivers online, if you enter your serial number it will point you to the exact driver. Don't have the URL but just look on the Netgear page.
Belkin also makes a small USB connector, for 25 bucks, I've always gone for Belkin over other network stuff because they have been around for ages.