We have one about 8'x8', speaking of small sheds, and it was positioned almost exactly in the middle of our small back yard, very poor feng shui. I finally got pissed off enough at looking at it that I decided we should move it. Several people told me to just buy a new one, but I couldn't justify that since this one was in perfectly fine shape, with minimal rotting at the bottom of a couple of pieces of T1-11, and why would I want to throw away $800 or more?
So I got some friends together, totaling 5 women and 2 men, and we lifted up this thing and moved it along some 4x4 posts that acted as rails on the ground. The job supervisor was a guy whose dad used to move massive gravestones with not much more than a couple steel rods, so he knew how to use leverage. We moved the shed about 10 feet to a spot right behind the garage that is about 10 feet wide exactly, with the garage to one side and a stone wall on the opposite side (and the neighbor's fence on the back end, hence no room for a come-along).
None of the Internet resources I found were any help for our particular situation, not even this: