Taking out asphalt is not a very technical job, just a lot of work. Most can be broken up using a sledge hammer, or you could rent an electric powered jack hammer. Its nice to use a bobcat to remove the debris, but prying up the pieces and moving them to a dumpster with a wheelbarrow can be done, it will just take a while. A heavy steel digging bar or spud, and a block to use as leverage will help. When all the asphalt and base is removed, expect to have a load or two of topsoil brought in to give you plantable clean earth.