To sort things out in an orderly manner, think about your repair work in three levels: basic, average and advanced. Before you purchase any tools, sit down and determine your present level of mechanical expertise. After you have determined that (be honest), determine just how far you intend to progress as an amateur mechanic. Knowing what you can and/or will do in the way of automotive repairs is the most important step you can take. Obviously, if all you ever intend to do is to change the oil and the plugs now and then, you won't need very many tools. If, however, you plan some extensive repair work, you're going to end up with a complete collection of tools.
Once you have determined your level of mechanical involvement, evaluate your tool purchases on a "must have" and a "nice-to-have" basis.