DesignFoil is worth noting too. It is on the much pricier side (inexpensive for CFD), but has pretty extensive CFD modeling including the "Virtual Wind Tunnel". I've tinkered with a much earlier version of this years ago. I didn't end up building anything, but it's a good program also. The software mentioned in the above post appears to be much better for the overall design work and ending up with the templates necessary for building (unless many new features have been added to DesignFoil since I used it).

http://www.storesonline.com/site/960...uct/DesignFoil