This is for the crazy few who, like me, run Windows in KVM on a Linux host. If you ever need to resize one of your Windows disk images, these are the steps necessary to accomplish this feat. (Please note the steps for actually changing the size of the disk image were taken from this linuxwave blog post) This works for Windows 2008 Server, and most likely Windows 2008 Server R2. I do not know if it works with any other versions of Windows.
Convert qemu image to raw
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qemu-img convert -f qcow2 imagename -O raw imagename.raw
Extend the image size using dd (In this example, to the size of 10G)