I'm looking to convert some libraries to use .NET Core. I used the Portability Analyzer to help me gauge the work that would be involved and it showed me that I will be much better off using the .NET Core 1.2. Unfortunately it isn't slated to be released for months, but I figure I can start looking at the beta in the meantime. I see the 1.2 beta on GitHub https://github.com/dotnet/core-setup/blob/master/README.md but I think this is only the runtime. Is there anyplace I can get the SDK?
When I originally posted this answer the time frame for release of .NET Core 1.2 was the first or second quarter of 2017. That has since changed. .NET Core 1.2 is now .NET Core 2.0 and the first preview is scheduled for the second quarter of 2017.
Follow the .NET Core Roadmap for details.