A couple additional tips for outsourcing:

If you are posting an account creation type project, make sure you get the prospective coders to submit a sample created account before you select a coder (and verify it!).

That will eliminate over 50% the bidders and 75% of your problems before you begin.

Always escrow the payment.

And as Kurt noted, sometimes outsourcing will take more time than doing it yourself.

A recent account creation project took me longer to verify the accounts than to enter the captchas myself.