I am making a very large Portal 2 Map, And i want to have custom models inside it, I am aware of Pakrat. But i need help actually creating the models. I can compile a .SMD Into a .MDL I need to know what software to use. I have Blender and Maya 2015. Any others?

I don't care how much the software may cost i just need something to create the Models.

anything that can make models can be used.
if it has a plugin to export to smd that'd be the best
As for some software you might want to consider:

• Blender
• Google Sketchup
• Maya*
• 3ds max*
• Softimage Mod Tool

just to name a few.

Any of them will do, and which one you use is totally up to personal preference.

*can get a 3 year free licence as a student.

Thank-You Lpfreaky90 For helping, I will use Blender. But One question, How do i give Blender models a custom texture?

You should try to find some Blender tutorials.