Hi Wolfke,
Welcome to the forum.
How far will the free courses take you? Really the only answer is to take them and see - each person is different, has a different starting point and a different desired end.
A driving test shows that you're safe to be on the road, but doesn't make you a formula 1 racing driver, and likewise you wouldn't expect a short hypnosis course to make you an expert.
When you refer to 'all the other downloads' are you referring to the downloads at
http://www.hypnosisdownloads.com/? These are actual hypnosis sessions by professional hypnotherapists, with a specific aim in mind.
The two formats complement each other well - some people like to read about things and learn that way, other people like to have the experience, and some want both.