I like the Olfa circle rotary cutter my friend recommended after seeing it demonstrated at the Houston quilt show.
I didn't have the cutter when I made my first yo-yos, so I cut a piece of template plastic the size required and traced around it--okay to do if you only need to make 12 yo-yos like I did for my project, but not if you need many more than that.
The yo-yos were centers for folded hexagon flowers in a small wall hanging I made several years ago, photos for which are posted in the "My Quilts" tab of my blog.
Good luck with your yo-yo project!