What amount of time is involved in Schutzund training, eg. is it a once a week deal or does it depend on the dog and owner?
This is the only question that I feel remotely equipped to answer, so hopefully some more experienced people will chime in on the others.
The time investment depends on you, your dog, your club, and your goals. From what I've seen, most clubs in my area require a minimum
investment of one day/week. That's the absolute floor.
But that's just club time. If you want to develop skill in any
sport, not just Schutzhund, you should be prepared to spend a lot more time than that practicing on your own. Exactly how long it takes will vary depending on your own training skill (in general, more experienced trainers are able to do things more efficiently), how quickly your dog learns and how intuitively he grabs onto particular concepts (I have one dog that picks things up at lightspeed and another who needs two weeks to grasp the simplest concepts; however, both of them have different strengths/weaknesses and are sometimes quicker or slower to pick up particular tasks), and how high you set your goals.
If you just want to teach your dog the skills and have some fun, that's probably going to be a smaller time commitment than if you want to title your dog but aren't too fussed about the scores. If you want to compete seriously and hit high scores, then it's going to be a much bigger investment of time and effort.