I have been developing professional software for around 15 years and i'm interested in exploring the possibility of working remotely within the USA as a contractor. My experience is broad but mainly in embedded systems, mobile development and graphics. I'm interested to know whether contracting jobs where i could work remotely are common and some good resources to use to find work. I know of some services such as oDesk and eLance. Are these good places to offer services or are there better alternatives?