Tip: Never do a domain availability check unless you intend to immediately register the domain.

When you do a domain availability check, squatters get a list of the inquiries, and they may choose to register the domain if you don't.

That's why my blog is at 'realfreemarket.org' instead of 'realfreemarket.com'. When I did an availability check for realfreemarket.com, but didn't register it, a squatter grabbed it.