I use a hand truck to move them around; i have one i picked up at costco that has pneumatic wheels and a ratchet strap the log onto it and move as necessary.
Granted; after that it is maul or wedge&sledge time ... but to move them it's all about the hand truck. I have had some pretty big rounds moved by myself this way [biggest being about 49" across in diameter].
The hand truck has helped me out too, big time. There are also dollies made for moving small trees with the root balls, landscapers use them. I thought they they may work well too, they have big ole pneumatic wheels. Before we had the log lift added to our speedco I would lay an 8' fiberglass ladder with the top wedged into the I beam and roll the big rounds up to the cradle one rung at a time, worked but still a lot of grunting. We found laying the big rounds horizontal on the cradle is somewhat easier to split into the first big quarters. The back is a terrible thing to waste... Anyone ever use a small jack hammer with a wedge bit?