Ask HN: Developer disappeared after his first payment..?

I signed a contract with a developer for X amount of hours of work. He completed the hours and I sent him the first payment, haven't heard from him since. Is this usual? I asked if he is interested in continuing work or should I find a new dev a week ago with no reply. Really don't want to stall on the project and it's close to being ready for launch.

Found him on HN through the freelancer thread. Any suggestions of a place to find good affordable developers for Django? I'm a front end designer, but need help with the back end on my project. Thanks.