HMH makes an inexpensive tube fly kit 20 bucks to get you started.
In that fly, I would run a plastic tube(the end of the ink resovour in a bic pen for instance) through the foam and have it stick out an eighth of an inch or so. Then I would slide an eighth of an inch of flexable clear tube(like from a fish tank) over that. This will hold a short shank hook in place so that the body can be as long as you want.
One cast can change your day...maybe your life.