Some stereo 3D shots from my hometown.
Techniques:
To see: start to cross your eyes. You'll start to see the full image (a pair of L+R) "doubling" into two pairs, one moving to the left and one to the right. Make the left part of the pair moving to the right perfectly overlap to the right part of the pair moving to the left.
To take: take a photo with the left eye, and then with the right eye :) possibly using a tripod.
Keep the same height and vertical orientation for both photos; orient the photos horizontally a bit towards a common point in the photo but not completely* (unless you want the point 2D like a far landscape).
Put the photo taken with the left eye on the right, and the one with the right on the left.
I say it gives decent results :)
* = not exactly the best thing to do according to the experts, but just let me experiment a little more ;)