Converting 22" LCD to touchscreen?

[MasterShake]

I heard you could find overlays on eBay that you could put over a monitor to make it a touchscreen. I'm having trouble finding the parts though and was wondering if anyone had done this before. I've seen guides on how to build one from scratch but I'm lazy and not really wanting to go through all that. I'd love to find an overlay for my 25.5" Samsung but I seriously doubt I'll be able to find that, at least at a decent price.