I have looked for similar data amongst the files before, and my best guess is that it is in one of the binary files, or which I know nothing of the structure. If you look in the CareerTrack.upc file and notice the start location, they use "scientific" number notation, and not a straigt-up number, so I don't know if you would have to look for the long/lat stored the same way in a binary file, or the regular decimal location data. If I'm not mistaken some of those files are encrypted, which would make finding the data rather daunting. Also, a BIG problem with trying to use the Save data is having the player put an executable in the correct folder to gather the required data... It might be easier to have a little pop-up that the player inputs his location into prior to exiting the game... ?? Of course, one has to be careful shelling-out to Windows from the game, since that can cause trouble on some set-ups.
P.S.: it might be that Jeff-Groves could think of a way to "search" through the Save folder binary data with the 010 Editor program, and might make short work of the search...