I consult on oDesk, yet I've yet to hire anyone, but people continue to ask me about the process. Lately I've suggested to people that if they don't know how to spec their req, they might want to hire someone who can.
It reminds me of the groups of people who always followed my father around at cocktail parties, hoping to get advice. He always said that there was no such thing as a free drink for him: Had I the experience, I think I might have prepared a document for him to carry so that he might pass it around events like this. Since I have a more tech-savvy clientele, I should be able to get away with posting a link ;)
How To Hire An Awesome Developer on oDesk: Part I