I believe that it is available to ADN members, members of the Autodesk Developer Network. I believe that provided access to the last three product releases. Here is more on ADN:
Thank you Jeremy. I had just watched many, many videos and was almost certain that the toposurfaces part was what I needed for a major project that I am about to start. After watching the toposolids videos, I am not as sure if the toposolids might possibly work but there are some things I'm not sure that I could work around. If I can't get the REVIT with toposurfaces I may need to look else where for something that work. The ability to move the contours freely is its best feature that I was needing. Are there or do you know of any other software that might fill my need? If so would you please contact me or reply to this thread? The job that I am working on requires a NDA and I'm sure that Revit would like their name on it.
I am not an expert on product recommendations, and I am also unclear on what your exact requirements might be. I do not think this is the optimal place to ask for recommendations, either, since this forum is dedicated to Revit API consultation only. Still, would you like to clarify what you need? Maybe someone here will have an idea for you.