Welcome to the forums!
Lots of good advice so far here! When it is all said and done, the Airstream you choose will depend on your lifestyle, number of people and pets, and your pocketbook!
But no matter what you will find lots of ideas here and you can ask questions about any little item that strikes your fancy about Airstreams! In the meantime you might check out this thread, it is a older one, but has lots of "food for thought" when looking for that perfect 'stream.
http://www.airforums.com/forums/f353...eam-22920.html
You might look at the Vintage Airstream archives to get an idea of vintage options and the floor plans/layouts compared to the newer ones. Besides, these are just plain fun to look at!
Vintage Airstream Photo Archives
Have fun! Good luck in finding just what you want! BTW, a rally is a great way to go to kick tires and talk Airstreams!