I have one of those non-reflective flat computer screens. There is no reflection from it. However, I found a small flashlight (mini-mag), turned it on, and pointed it at the screen. That worked. I was able to stare at it and eventually see a few stereograms. Be warned though, not all stereograms are created equal. Many of them are very hard to see, at least for me. Others are easy. I believe there are a few different techniques for making them so that could be the difference. I’m in the process of anchoring the photofocus state so that I’ll be able to get into it on demand, but so far I still need the flashlight and I can’t do it on printed papers yet.
Try http://www.eyetricks.com/3dstereo.htm. These seem to be some of the harder ones for me.
An easier site is: http://www.softsource.com/softsource/stereo.html
Good luck.