How do I make a mod? Help please, greatly appreciated!

[Jeff Benzos]

So I wanting to edit some objects in Left 4 Dead 2, like interactive objects just so I can make the game look different the way I want to. I was also wanting to change how the zombies look. If anyone could help me with this, I would be in debt to you!
P.S I already have Left 4 Dead 2 Authorization tools, is it something on there??? I would be led to think so.

[GLAZZMAN]

http://l4d2.gamebanana.com/tuts/10827

gives you the basics.

Tips: when it says "extract everything", only extract what you need. And dont worry, GCFscape and VTFedit are totally free and have NO viruses or malware or anything. I use it, and everybody else who mods does

[Jeff Benzos]

Sweet, Thank you so much!