Craig's List would be the first place that I would start. Just know that you typically will be paying more to receive owner financing. Most sellers would rather have cash (conventional financing is cash in the end). The seller may feel that this is the only way to sell their property, or they may be in the business of buying homes and reselling with their (owner) financing. I would think it would be best to have someone at least review whatever you are looking at before signing on the bottom line for your dream home.
It might be good to look at other methods of financing. A good mortgage broker will know of several alternatives. A knowledgeable real estate agent will know several lenders and the different programs available.