It's not a difficult hobby to get in to. Go to your local home and garden store and choose a plant with a woody and interesting looking trunk for a few dollars. It only cost me about $10 to throw together a tools-kit. Look through the manicure and nail-care section to find things like small cuticle scissors for pruning. An exacto knife is handy, or a scalpel. Small wire snippers, and a couple spools of thin wire.
A small juniper bush is a good first choice, but you can use a wide range of plants. They can be flower bushes, or fruit trees (you can have a tiny little cherry tree that will grow fruit on your desk). It's a very cathartic hobby, extremely relaxing.