We are in the process now of doing our Winter dormant fruit tree pruning. We have four tools that help with this task: 1) Fiskars hand pruners, 2) Pole pruner, 3) Pruning saw, and 4) Loppers. All of the new bare-root trees that we are planting get a hard prune to about 30" high. This low top pruning will encourage strong low side branching.
Deciduous fruit trees that are just a few years old are being shaped into an open vase shape. We remove upward water sprouts that are growing straight up, we remove all crossing or dead branches, we remove growth in the center of each tree, and trim back long branches to a strong outward growing bud.
Deciduous fruit trees that do well with dormant pruning in the Winter are apples, plums, pluots, pears, nectarines, and peaches. We will wait and do a Spring or Summer pruning of the apricots, apriums, and cherries.
Evergreen citrus trees will be pruned after the weather has warmed. We shape them to also have an open center and bushy shape.
UC Davis has an excellent publication that teaches how best to prune fruit trees: http://homeorchard.ucdavis.edu/8057.pdf