I have searched EVERYWHERE that I can think of with no luck 1990 Honda CRX base or hf model manual window reg?

I'm not sure if I can fix the one I have. I bought the car new and it is the original regulator. Any suggestions would be greatly appreciated.

You'll have to remove the door inner panel to inspect first for the reason why the window does not work. It could be the window glass was separate from the regulator or the regulator need to be replace or anything else. This video will show you how:

A sample of the window parts that you may need:
http://estore.honda.com/honda/parts/view-honda-parts-catalog-detail.asp?m=1990-crx-2-si-5mt&b=B++52

Since you didn't specify WHY your window regulator needs to be "fixed," it's hard to suggest a repair… Perhaps you should take the car to someone who deals with that sort of problem and find out if it CAN be repaired.

About 10 years ago, it got really hard to roll up or down, getting stuck so I had to either push or pull the glass while turning the knob