I performed a WHOIS search on phoenixgarage.com, and the domain was found to be available. Further searches on the .org and .net variations showed that they, too, were available. I grabbed the .org domain first, and followed with the other two at a later date.
I had decided that I would use the .org domain because it seemed more in line with what I wanted to accomplish with my site - it felt like a "non-profit" endeavor. The other two domains were parked for other uses (right now they show an out-of-date redirect page to this site - in fact, they are so out of date, they still list my indirect.com email address as being current!).
I figure that someday I might use either the .com or .net domain addresses for a business or something, if someone doesn't come to me with an offer I can't refuse.