Here is a complete list of Language Interface Packs or LIPs available for download, for Microsoft Office.
With Office Language Interface Pack (LIP) packages, desktop users can experience frequently-used Microsoft Excel, Outlook, PowerPoint, and Word features in their native language.
In addition, the packages allow users to switch between the LIP language UI and the full Microsoft Office program language UI installed on the user’s computer.
Do note that it is mentioned there that these downloads apply to:
Microsoft Excel 2010, Outlook 2010, PowerPoint 2010, Word 2010, Excel 2007, Outlook 2007, PowerPoint 2007, Word 2007, Excel 2003, Outlook 2003, PowerPoint 2003, Word 2003.
– List of Language Interface Packs (LIPs) for Microsoft Office.
– List of additional international downloads.