Typically the properties without a number are being fed to Trulia through RealtyTrac - a company that tracks foreclosures, preforeclosures etc. They do not release the full address unless you have a subscription with them. Your best bet would be to contact a real estate agent to track down the information for you and can assist you in placing an offer, if the property is even on the market. A buyer's agent is key when looking at these types of properties and they are paid by the listing agent. If I can assist you with anything let me know.