Some ideas: 1) Start by checking your town's ordinances, as speed limits may be codified for certain areas (e.g., all residential areas 20 MPH), although any such ordinances may not be accurate or up-to-date. 2) Check with the town's public works department or road department; there may be records of sign placement or speed zones. 3) If your town is covered by Google Street View, you can digitally "drive" the streets looking for speed limit signs. Avoid big "jumps" as it is easy to miss signage in Street View, and do check streets in both directions, whether in Street View or in the field, as speed limits are not necessarily the same in both directions for any given segment. 4) If all else fails, hit the road with that GPS unit; ultimately, being there will produce the highest quality data. Aloha, Andrew Irwin, Maui County Geographic Analysis & Cartographic Services (GIS), Wailuku Maui.