The srv_gmod_9_0.zip file you have requested: Garry's Mod / Half-Life 2: Garry's Mod Server Dedicated Server Files - 31.35mb is not available. Perhaps try browsing all files for the game Half-Life 2 and upload any files you want to share or are missing. This is the only information we could locate:
With these files, you are able to make dedicated Garry's Mod Servers. This is for Linux & Windows.