Well, you didn't specify a modeling software package so I will assume the free one.
You can get Blender and all the necessary software
here (included install info and other useful tools)
Once you get everything installed and working properly, I would then suggest going through the "Noob-to-Pro" tutorial on
this page. It is pointless to try and do anything with Blender related to Oblivion without first learning the interface and basics of modeling. You can practice on things such as swords and shields but try to keep focused on learning how to navigate.
After a week or two of just playing around in Blender and getting familiar with it (be sure to go thru
these video tutorials), I would then suggest learning some modeling techniques that you will need to make Oblivion models such as the following:
* UV Mapping (
Text-based tutorial,
Video-based tutorial)
*
Importing and Exporting Armor in Oblivion*
Custom Helmets in Oblivion*
Weapons with Multiple Collision Objects*
Custom Sword in Blender*
Custom Shield in Blender* Custom Cuirass in Blender -
Part 1,
Part 2*
Easy Rigging in BlenderYou do not really need to read-up on the following topics in relation to modeling for Oblivion:
* Materials / Lighting / Reflections
* Rendering
* Simulations
* Particle system
I suppose I need to refine this and make an article about "
Start Modeling for Oblivion with Blender"