I found the voice pack collection at ProjectAI.com http://www.projectai.com/library_archive/ufiles.php?cat=4and just wonder what they do. (in a nutshell).Is it just ATC using the airlines names?

By default FS only has a couple hundred airline names.EVP - EditVoice pack is used to add additional airlines, types of aircraft, aircraft manufacturers, airport names to FS.I would recommend you go to the source - http://www.editvoicepack.com/ - and try the program for your version of FS.

...adding to what was said, last time I checked, the FSX version of EVP does not yet have the capability to add new voicepacks to it.You can, however, use FS9's EVP to make changes and then port over the USEnglishBig.gvp file into FSX.RhettAMD 3700+ (@2585 mhz), eVGA 7800GT 256 (Guru3D 93.71), ASUS A8N-E, PC Power 510 SLI, 2gb Corsair XMS 3-3-3-8 (1T), WD 150 gig 10000rpm Raptor, WD 250gig 7200rpm SATA2, Seagate 120gb 5400 rpm external HD, CoolerMaster Praetorian