I used my handy-dandy Japanese saw to cut up the PVC pipe. I ended up using three ten foot sections of half-inch pipe, four elbows and 24 t-joints. I decided to glue the top and bottom sections because I didn't want them to slip but left the verticals unglued so that I can take it apart for storage. I also didn't glue the small posts that stick out from the top and bottom sections so that I can pull them out to get the skein off the frame or even rearrange them to make skeins of different lengths.
So here's the finished frame. I'm going to give it a try today and see if it actually works! I'll take some pictures of it in action. If people would like a full description of how I made it, let me know and I'll post it.