where would one go to find a new/rebuilt turbo for these diesels specifically the 1.6l TD or even some of the newer ones...
When I had a problem with my Garrett on my 1.6TD, I researched the possibility of finding a new /rebuilt unit, but the few places I called didn't seem to carry any. One place did have a listing and a price, but couldn't actually get one.
For me, my best option turned out to be rebuilding another used turbo that I had from another TD I picked up as a core. The local diesel / truck shop got all the parts / rebuild kit and did the work. It came back looking brand new...
You might try searching ebay for rebuildable cores or the classifieds on sites like this. You could also search out places that deal with Garrett turbo's and maybe even some VW specific shops like VW Diesel Parts here in Ohio.. (no affiliation)
http://www.vwdieselparts.com/center.htm
It seems that rebuilt or new turbos for the 1.6lTD are no longer available through the VW dealer. (Not that you'd want to pay their exorbitant prices anyway.)
You could call around at the various turbo rebuild shops. Some keep an inventory of rebuilt turbos ready to go, or rebuildable cores they can build for you on request. Who knows, you could even happen across a brand new one. The identification number for the Garrett turbo off the 1.6lTD is "TA0304B", and the 1.6lTD KKK turbo's ID is 53249706080. As just one option for a turbo rebuild shop, you could try this place, I know they have a lot of inventory:
http://www.adpdistributors.com/There is also e-bay, this board's classified section, etc.