I have sucessfully replaced my cracked touchscreen using a cheap Hp iPAQ 1940 h1940 1945 h1945 Touch Screen from ebay. The item number was 190557941601. The cost was less then $10 delivered from Hong Kong. I had read in other threads that the cheap Hong Kong touchscreens don't work, but this works perfectly, I didn't even have to calibrate it.
Fire seperate the remote. Remove the display from the main PCB, it will be necessary to desolder 2 solder joints. Carefully remove the old touchscreen from the LCD by prising it off the display using a knife & clean of old adhesive. Remove protecting layer of new touchscreen, exposing the adhesive & attach onto the LCD, taking care to align correctly. Check alignment my placing blue casing over the touchscreen. Note that the touchscreen is slightly smaller then the old one, & some of the border will be exposed withing the display window. This isn't a problem.
The hardest part is soldering the touchscreen flexi onto the main remote flexi, not a job any DIYer is capable of I'm afried, but using a large flat spade tip that covers all four joints will do the job with care. Remove the old flexi by heating carefully, apply a little flux. Tin the new flexi, offer up to mating flexi & apply heat using the flat tip spread over all joints. Timing & temperature is crucial here, not enough & the joints won't bond, too much & the flexi will melt.
Hope this helps someone.