Good for you!! Enjoy the freedom to have your own bigger space and design it as you want it. And don't forget a space for a popcorn popper-they are such a big hit this year. My DH keeps telling me I can have the family room downstairs along with the 2 bedrooms I already have, but I would be tempted to take out the fireplace in order to have that wall space too. So, I've never done it.
We have used these 2 sites to plan a 3 season room that just hasn't happened yet.
http://www.americandrew.com/planner.asp
http://freshome.com/2010/08/18/10-be...ams-and-tools/