I bought a box of 100 Screen Cleaning Tissues for TFT, LCD, PDA, Laptop and Scanner screens from PC World for £4.99. The brand name on the box is STOREX
Try a search on Amazon.co.uk for "screen cleaner" in "Electronics and Photo" - it pops up half a dozen options.
We've tried a few and they all "work" in that they at least smear the fingerprints out to such an extent that they don't show, but I haven't got anything I'd say is great
When I used to work I installed touch screen terminals and found the best cleaner was plain carbonated water, just a touich on a tissue cleans 'em nicely.