PLTS for ArcGIS - Foundation 9.3.1 could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. The program is included in Photo & Graphics Tools. The actual developer of the program is ESRI, Inc.
We recommend checking the downloaded files with any free antivirus. The most popular versions among PLTS for ArcGIS - Foundation users are 9.3 and 9.2. This PC program operate with the following extensions: ".gnd", ".mxd" and ".mxt". The most frequent installation filenames for the software include: ArcGlobe.exe, ArcMap.exe, PLTSDataLoader.exe and PLTSDesktopAdmin.exe etc.
From the developer:
PLTS for ArcGIS -Foundation is a collection of turnkey software applications for highvolume
database production, maintenance, quality control, cartographic product generation, and workflow management. These applications, developed by the ISO 9001:2000-certified ESRI Services Production Group, facilitate every step in a geographic information system (GIS) production process.
You may want to check out more software, such as PLT Scheme, ArcGIS for AutoCAD 300 or ArcGIS Editor for OpenStreetMap, which might be similar to PLTS for ArcGIS - Foundation.