Honestly I would say on freelance websites like www.guru.com Get work though sites like that and not try to get work through your website. It is very difficult to rank for web design websites so I wouldnt even try.
Guru.com stinks. It is just a bloated mess of out-dated freelancers. I would suggest adding the link to the site in your sig and post away. Also, write a few articles regarding web design and then in your bio plug your webdesign site. Check out http://www.adotas.com and inquire about writing an article. I've done a few for them and I've received a great response.