[guide|13445|THIS GUID]E will assist you in opening up the BB.
It looks to me that the digitiser/touchscreen is part of the LCD so you probably need to replace that entire assembly
'''Step 12 from the guide'''
The display unit is ultra thin, a feat achieved by some serious fusing. The digitizer is applied directly to the glass and fused in turn to the LCD.
[http://www.ebay.com.au/itm/LCD-Display-Touch-Screen-Glass-Digitizer-Assembly-for-Blackberry-Z10-tools-/221205876473?pt=US_Cell_Phone_Replacement_Parts_Tools&hash=item3380e5cef9|From ebay]
[http://www.etradesupply.com/blackberry/other-models/blackberry-z10.html|Google search]
I cant vouch for either supplier.