If you use the search feature you will find that there are many discussions about building revolves. I believe some even have some drawings associated with them. If you can't find what you need with a search, then you will have to give us more details for us to be able to help you. Things like what show, how big a revolve, what your budget constraints are, how long the run is, etc.
Also, stop by the New Members forum and introduce yourself, we love new people!
I just built a 22' stagerevolve for my school's production of Jekyll and Hyde, If you want I can send you pics of the construction and some specs from the build. I also just posted a thread of what not to do when building a revolving stage...thats in carpentry.
As Icewolf said, there are a number of detailed threads on the construction of revolving stages. As I remember, Van came up with some pretty good plans. Do a few searches and you'll get some good results.