I'm not sure if this advice is on Trulia, but I do know that agents and Realtors are good resources for you. You should also conduct a search (ask the local chamber of commerce or builders' association or on the internet) for real estate development and/or investment groups. Our broker has a new development section in which they help a building owner through the process of converting an existing building such as yours into condos. There may be a large brokerage in your area that does the same. If you don't want to work with a real estate brokerage, try and look for real property investment groups. Lastly, a real estate attorney in your area might be useful to speak with as they may know contractors, investors and laws that affect your decision to convert your building.