Guys, please - never pay ANY artist money for work they haven't done. It is industry standard to receive the completed work, and all revisions, before the artist can even invoice (let alone get paid). I'm not justifying Josh's actions at all, but you should never feel like you need to pay someone before they can begin a project. That's just not how it works, and any artist telling you that you need to pay them first is taking advantage of you.

Bit of an update on the situation as well as reply to Adam's posting...

Adam,  I have been on the both end of being a client and an artist in the gaming industry numerous times.  I know you are familiar with working with people on different size projects. Big projects often require some percentage of payment up front...  Small project like this situation with Joshua... I would probably wait until the project is done.  Not knowing Josh's past record...  I just felt bad about his situation and decided to give him a chance.  Which backfired.  I also have a famous artist take large sum of money and just completely not delivering...  ended up jeopardizing the entire project... 

With Josh... he did get back to me via Skype once saying he is doing work.  I requested to get in touch with him for updates and communication but he has completely disappeared.  I was going to pay certain amount and demand the rest back.  But at this point, this is serious breach of contract.  I will have to ask for the full refund.

All this to say... more things like this happens to the client, it's not good for the all the artists.  Reasonable clients will always negotiate with terms of payment.  But more things like this happen, it will be harder for artists to have flexible payment method...