[russelluresti]

Freelancing is all about relationships. If a possible client is looking for a freelancer to complete a project, the only difference between Developers A and Developer B is their price (because, the client isn't going to understand the skill/talent of the two developers - they're not developers themselves). But, if you're able to form a relationship with them, then you're not Developer A anymore, you're James. And there's a HUGE difference between James and Developer B. The client knows James, the client trusts James. The client knows James wont' screw them over.

So, I'd say make your approach a very personal one. Try to get them invested in you as a person. This will be difficult to do with those "one-off" jobs, but will work great for clients that have multiple projects that need to be completed. It also works well if you work as a contractor for local agencies (as suggested by @iantrerell).

Also, a decent source of information is Freelance Switch (http://freelanceswitch.com/).