Elance is probably the best freelancing portal in my opinion. I saw somebody posted about Freelancer and both are good sites, but Elance is easier to get work as you don't get as much competition from Eastern countries where people will generally be willing to undercut you.

Elance is probably the biggest freelance site out there and has thousands and thousands of jobs available at any one time. If you register with them and let them know what skills you have and what type of work you would like to do, they will alert you with new job opportunities. There's that many that there's always something for everyone, and once you have build up your reputation a bit you can get some pretty well paid and good work.