After reading the first post in this thread I became concerned about finding enough wood to finish my own UFO build! With the help of Clay at the [link=http://www.thebalsastore.com/]The Balsa Store[/link] and the folks at [link=http://www.nationalbalsa.com/]National Balsa[/link] I was able to come up with enough wood to finish the UFO and build my next Classic Pattern Model, whatever that might be!
I talked with Clay for quiet a while and he was very helpful. He seems like a good guy that will do whatever he can to get you the wood you need.
I also talked with someone at National Balsa, but I can't remember his name. Eric maybe?

Anyhow, he told me everything that is listed on their Web site is in stock! He also said that getting contest balsa is not a problem. What is a problem is getting it in 48" lengths.