The first soundtracks were created in April 2003 for the presentation at E3. These soundtracks were HL2_song 0-14 and they still exist in final game. There are 3 soundtracks that which are not used in the game but they were created in late 2003 - early 2004.
These are:
Combine Harvester: was originally supposed to play somewhere in the Citadel;
Miscount Detected: was supposed to play during the aborted teleport sequence in "A Red Letter Day";
Headhumper: was originally supposed to play when the player is ambushed by a Headcrab while exploring a zombie-infested shack during Water Hazard.
The soundtrack you send here is not a fake and was created in march 2001, but its probably a test one since his file location in beta is
sound/temp/music_test, so most likely it shouldn't have appeared in the game.