Q.How do you winter a young pear, apple and willow tree
I have checked online and get different answers. After reading your site I trust you more.

Certified GKH Gardening Expert
Unless you have something specifically for warm areas, then there will not be much need to winter them at all. I only recommend special treatment during the first year of its life. If this is a grafted tree that was purchased, and designed to fruit very soon after planting, then these trees will be ready to winter as long as you have gotten them in the ground and they have established already. This includes the willow. It will be hardy as well (and can become invasive).
Can you tell me a little more about the age of the trees, and about the environment that they are in right now? Pictures can help as well.