Hi Steven,Like I said on GIS.SE (GIS stackexchange website), set the coordinate system of the latitude-longitude data to NAD 1983 (geographic coordinate system, North America). You need to tell the software what coordinate system the points are georeferenced to now. Then ArcMap can project the points on-the-fly (in-memory) to the data frame's coordinate system. Once they're lining up correctly, if you want to save the data as a feature class, right click the layer in the table of contents and choose data, export data. That tool will give you the option of writing out the points in their native coordinate system (lat/lon) or in the data frame's (State Plane). Hope this helps,Melita