Thank you for all of the replies.
Astroman, this is a 10x20ft. Fortunately I do not need any city approval to do anything on my property. I bought a house that strangely lies in between city border lines. So I could probably drill an oil well and there's not much they could do about it.
I will certainly be looking at Google Sketchup!
Mike, I am really considering the Skypod. Whatever I choose, it must be able to sustain very high winds (70mph+) and high heat (110-115F). Snow is not too much of a problem, although it happens. We get a lot of tornadoes, and I live on a hill, so wind is the main concern. Although I know that only steel or very heavy brick would stand a chance against an F1 - F3, so there is only so much I can do there.
Ken, the observatory sketch looks great! Inspires me to get started.
Now, to start saving up for the bling!
Art