I used the closet organizer things you can get at Home Depot, getting 4 vertical "tracks" in 12" length. I then got the pieces normally used as shelf supports and used them as saddle racks -I think I did 18" on those, and also got smaller supports of 6" or so, too.
The tracks were mounted vertically, and the 18" support put at the top, with the 6" support put a few inches lower. I use the smaller supports for stirrup leathers and girths.
I did two rows of two racks, and then but a bridle rack to the right. I'll see if I can figure out how to link to the picture. Not sure if FB settings will allow you to see it, let me know if not.