At the moment it is not possible to create the SD card on Windows. So for now you will need a Linux system to do this, you can use a VM running under VirtualBox, se the Wiki pages for more details. Once you have a working SD card you can use Windows to develop programs. See this thread:viewtopic.php?f=18&t=4764
for details. Alternately you can use the Linux VM you created to build the SD card as your development environment (this is what I do).