The Design Update: Making the switch from Full-Time for a company to Full-Time Freelance

I'm a pretty darn good web designer with 6 years professional experience, but too many times I've felt very constrained and had my hands tied by companies who have hired me. I am interested in doing freelance work, but have always struggled getting my feet under me when starting out.

Looking for anyone's input who's done this, and specifically the best way to find new clients.