SSDT CTP4 is now available for download in our full language set. Download links are available directly on our download site. This page can also be reached through the SQL Server 2012 RC0 Installation Center. If you have already installed SQL Server 2012 RC0 with the SQL Server Data Tools feature, then the SQL Server Database Project stub will point you to our download via WebPI.
If you have previously installed SQL Server Developer Tools CTP3 (Code-named “Juneau”) and plan to upgrade to SSDT CTP4, please follow the instructions laid out in the “Uninstalling SQL Server Developer Tools CTP3” blog post on the SSDT Team Blog here.