Check with all the local theaters, big and small. My school did Noises Off this past spring. For the set we got plans from a major theater (Meadow Brooke Theater @ the Oakland University Campus) affliated with some of the largest entertainment venues in the detroit area. My TD made sure the set would fit the
stage, and he also made sure the set could make full 180's on our
stage. This is one of the hardest sets to
build, we finished the set fairly late. There should be plans you can buy/get. Since your interested in buying, you should probably check with every theater in your area that has done this show. You could perhaps check with one of touring productions of the show. Try contacting a pro staging or scenic group. This show is a benchmark in comedy, everyone in the industry is somewhat familar with it. It shouldn't be too hard.