Adding new assets (models, textures, etc [but not maps]) to HL2

Heya,

It's been a while since I posted here or touched Half-Life 1/2 (in 'that' way O.O ... ), and even though I was firmiliar and had experience with this subject before, though as it's been a while I don't remember how this is done (I also read somewhere that Valve have changed the directory structure of HL2 & Episodes 1 + 2).

I've been dicking around with Hammer recently, and was keen on knowing how one could add new assets which I have already made, to be readable by the game in a custom chapter or so.

I am already firmiliar with modelling, mapping, texturing and skinning from both IDtech engine games or its subsequent deviations aswel as all Unreal engines, though I'm not 100% sure how models are setup with their physics/collision/material arrangements and all in Blender (the tool I use), or however they are setup.

I hope my thread qualifies as eligible for this forum database and I haven't asked too many questions, though any help is still appreciated.

Thanks in advanced.