My experience is that is't hard to raise your rates to an acceptable level with Elance or Odesk. After a couple of gigs you can get away with charging double that amount, but it won't be worth the trouble. At least not where I live.

My best gigs all came from my network. While starting small on Elance or Odesk isn't worth it IMHO, starting by building something small for someone you actually know is very valuable. Underpromise, overdeliver and let word of mouth do the rest.