Ah, OK, glad I asked you first Billie :-)
Can you suggest a bundled kit of components that would be suitable for your software (Arduino + Touch Screen Display + SD Card Reader)?
I found this on e-bay too....
http://www.ebay.com/itm/3-2-TFT-LCD-Shield-Touch-Screen-w-TF-SD-Reader-for-Arduino-Mega-2560-A080-/251117559109?pt=LH_DefaultDomain_0&hash=item3a77c5dd45#ht_6683wt_1029
and this....
http://www.ebay.com/itm/SainSmart-3-2-TFT-LCD-Display-Touch-Panel-SD-Slot-For-Arduino-Mega2560-R3-US-/271236277942?pt=LH_DefaultDomain_0&hash=item3f26f126b6#ht_4329wt_1161
And as you mentioned it, it may be that my application does not require the SD Card Module.... have you found being able to store and replay the data is of value, particulalarly for a non-experimenter like me?
And yes, as a future add on, a dedicated Arduino Ethernet shield would be a much more flexible solution.
Thanks again !