I checked on Ebay, there are about 7 listings for the touch screen/digitizer. Not positve if this is what you need, another member with the T100 may have some advice. The T100 is quite new on the market and parts are most likely hard to find. This is a link to one of the listings. I have no experience buying Asus parts via Ebay.
You can search for Asus T100 touch screen and several should turn up, I think they are almost all located in Hong Kong. Good luck.
New Orginal 10 1'' Asus Transformer T100 T10TA Touch Screen Digitizer Panel | eBay