Have you tried changing the default path for docs to point to your d drive?
Start>then user name to bring up your personel folders, right click My Documents and select properties, location tab and then move, point to your d drive documents and then choose copy to transfer files that are there to the new location. (Saying yes copies any docs you have in the default including the hidden files that make the new locations icon the correct one) Once this is done the index will work without you having to add it.
Hope that makes sense...
Basher