Read original post at Kunal's Blog
As mentioned in yesterday’s Windows Phone 8 launch event, Microsoft publicly released the WP8 SDK for developers. You can now build apps targeting Windows Phone 8 devices. You will be also able to program for Windows Phone 7 devices in Visual Studio 2012 now.
In this post, I am sharing the downloadable links of both web and offline ISO versions. Go through the System Requirements first before downloading and installing it.