The sawmill idea came from Matthias Wendel (woodgears.ca) where he builds a lot of his own woodworking tools. He transformed a 14" bandsaw to lay horizontal and put it on a 'sled' type of frame. It can cut fairly good sized logs as is. He has all of the plans and video of his build.
I'm not sure I'd make it exactly like his, but it's certainly a jump off point for the project. Ideally, I'd like to have it a little larger and have it adapt or be adaptable for a pull behind trailer to go offsite with it.