I saw something similar in a magazine that could be purchased. Well, you know me, if it can be made I'm going that route. LOL We started with a 5' length of 2x2 pine board. Then using a keyhole bit we routered out a well about 1/4 inch deep for the PVC to nest in. Then we cut the PVC 2.25 inches and pushed one down into each hole. They are not glued in... they fit snug just worked in. When you turn the Stickles bottles upside down, you get about a 1/2 inch of the bottom of the bottle showing, allowing you to see the color and have room to get a hold of it.
If I remember correctly, there are 27 tubes for Stickles. I have added a couple basic colors of acryclic paint. Because this sits flush against the utility cubbies, I had to take the pliers out of the cubbies (the handles were in the way of the stickles holder) and have put them as well as my punches in some of the empty holes.
I'm hoping with the colors out in front of me all the time, I'll think to use them more often. I have a rack of 6 basic colors for the mixed media table, too. I'm think when I get the Studio and begin decorating, I'll paint and wrap the tubes for a little color but for now the plain PVC tone will work.