>>264303294
crowbar for decompiling, vtfedit for extracting the textures and blender source tools for importing into blender

https://developer.valvesoftware.com/wiki/Blender_Source_Tools
https://steamcommunity.com/groups/CrowbarTool
http://nemesis.thewavelength.net/index.php?c=178#p178

its pretty simple, although i've only done it for gmod.