What Software do I need?

What software would I need if I were making a custom model, or changing an original model??

A modeling tool (XSi Mod Tool, 3DS Max)
The Source SDK
Preferably a GUI compiler as the Source tools are a bit of a pain.
GIMP, Paint.net, Photoshop to make textures
VTFEdit to get the textures in Source.

Ok, thanks