I don't use job boards too often any more. One of the ones I like, however, is Pro Blogger. There's another one at Freelance Writers Den, but you have to be a member. The beauty of it is, Carol Tice teaches writers how to make a living from their writing. She teaches them how to market themselves, get clients, network for business, find a niche, and everything a writer needs to know to position himself for maintaining a viable freelance writing business--even how to charge customers and raise your prices when you're ready. I highly recommend her membership site. It's cheap compared to the alternatives.