From Valve Developer Community
Warning:As of December 29th 2004 update, VTF2TGA is no longer compatible with format changes.
An older but functional version of this program is still available here. To use this version directly, place the VTF file to convert in the same directory with
vtf2tga.exe application, and in the command prompt type:
vtf2tga <Your VTF file to convert> <The resulting TGA file name>
- VTFEdit - a more flexible third-party alternative to VTF2TGA.