Download 17 User Interface (UI) Language Packs for Windows Vista
Microsoft is offering Windows Vista users no less than 17 User Interface (UI) Language packs designed for integration with the operating system. However, the company informed that only the 32-bit editions of the latest Windows client can have LIPs implemented. In fact, the Language Interface Packs are restricted only to the English language versions of 32-bit Vista, with no support for the 64-bit variant of the operating system or for previous Windows releases. The 17 LIPs can be installed on Vista Home Basic, Home Premium, Business, Enterprise and Ultimate, but only 15 of them also play nice with the Starter SKU.

 Windows Vista Language Interface Pack can be downloaded from here.

Source : here