broadaxe handles are not an easy piece to cut. one thing you might try is to find a medium size hardwood tree(ash would be good) and take your handle from the bottom of the tree, where the wood flares out toward the roots. The grain has a natural bend here, which will help, but cutting the actual shape would be hard to describe.
If you search the tool forum for "broadaxe" you will run across some posts by northern hewer, and I beleive he has some material available to show how the handle is cut.
