Bill: That door stop is a pretty good idea. Thanks.
Rick: that's very cool. Thanks for posting the link.
I've thought about using case fans, the good ones are really quiet, but I'm wondering if they can push/pull enough air to be effective on something as large as my booth. I'll give the fan issue more thought.
Other notes:
Bought Rod Gervais' Home Recording Studio: Build It Like The Pros today at Borders. Honestly I was surprised they had any in the store. I bought the only copy.
Also picked up some fabric at JoAnn's for some absorbers. I'll have to post pics when I get them hung.