Download New MS Filter Pack (2007 Office System Converter)
For default Moss / Wss already have facility to do searching and searching which is done can from list whatever available and also document already being uploaded on Moss / Wss.
Now Microsoft already submit new installer for update ability to search new extension. Specific document formats are .docx, .docm, .pptx, .pptm, .xlsx, .xlsm, .xlsb, .zip, .one, .vdx, .vsd, .vss, .vst, .vdx, .vsx, and .vtx.
For download this IFilter you can click this link : http://www.microsoft.com/downloads/details.aspx?FamilyId=60C92A37-719C-4077-B5C6-CAC34F4227CC&displaylang=en
For detail info Knowledge Base Article you see this :