I have an ambition to create . . being somewhat of an artist at heart, with some intelligence however little to no techie ability.

Seriously, I would like to decorate my Sims3 desert bred horses more appropriately and at times fancifully.

I have in my utilities folder:

Blender
Delphys

CTU
Custard
Dashboard

GIMP
CC Magic
Paint.NET S3PE UIC (zindagoldensims)

I also have TSRW
I don't want to clone, I want to create.

I went thru a few different tutorials and looked through a web search on how to create a horse model (which I'm thinking is necessary to put the pieces I want to create on) with no luck.

I'm thinking I have the tools (in myself and my system) to complete the pieces I want to create... I just don't know how to begin.

(See? I can't figure out how to tab items without that break after them.)

every creation start with a clone from a existing game item wether it is a CAspart or object.
I recommend tsrw for beginners wich has a full guide on how to get starting:
http://wiki.thesimsresource.com/ind...ry:TSR_Workshop

The thing is.. at least 1/2 of what I want to create isn't in the game, so how would I clone it?

I don't understand.

custom rain sheet
another example of rainsheet
with additional examples being
the Arabian tack here

This is ambitious but driven by passion . . I only need to learn how.
As they say, the first million is the hardest to make. lol