I downloaded Image Server 10 Development Kit from following url but could not find any dlls mentioned in its help doc. Also, I installed ArcGIS Enterprise 10 with Image Server Extension.But still I didn't find those Image Sever Client dlls like ISClient.dll. Where to get them then??
You'll find them in (default) c:\program files\arcgis\imageserver10.0\bin
Also, when installing the "Image extension" did you install something separately from ArcGIS Server (called ArcGIS Image Server) or just license it with ArcGIS Server. Because this is not the same thing. http://resources.arcgis.com/content/imagery/10.0/arcgis-image-server