....there are one or two Flight Sim Sites who use Google maps to indicate which Pilots are on line at the time.....
.... but the only GPS Radar Map indicating the position of all Pilots in a Multiplayer Session in real time, using FS Host, as far as I know, is "FS Navigator" for FS 2000/FS 2002/FS 2004.
The details will appear in the "FSHost Server Status" browser (when populated).
Paul...G-BPLF...FS 2004...FS Navigator*.... 8-)...!
* ....Unobtainable now...

...!
Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.