When starting from scratch: post on Freelancer Seeking Freelance every month.
You'll reach a groove once 120% of your referrals are word of mouth. The pendulum flips quickly between looking for clients and then getting a good rep. for doing good work and the clients flowing to you. Good work is hard to find.
With that said, don't negotiate for the highest rate possible at the start. Getting a good rep. will get you better paying clients a lot faster.