VISA 189 CONDITIONS FOR Canadian Physio to Australia...??

Hi, I'm a Canadian physio currently working in Australia under a Working Holiday Visa. I have a couple of months left on it now - it ends July 7th/2013....I have been debating and think I do want to stay in Australia longer as I am not ready to leave yet. I am 31 so there is no possibility of extending a working holiday visa (I don't think I can do that anyways as a working professional) - so my 2 obvious options are to 1) Get sponsored (the most usual route) OR 2) Try to get a 189 Independent Skill Select Visa...I do have options for sponsorship so I don't think that's a major concern - however to be honest, there are other avenues of work I want to pursue...I know with sponsorship you need to be working 38 hour weeks and I would love to work a little less (maybe 30 hours) while pursuing some Health Consulting part-time work of my own endeavour/"business"...but I can't do that under sponsorship.

So, my question is: what are the specifics of the 189?? Does anyone know? I read all the rules to apply for, etc. but it does not indicate anywhere how many hours of work you need to work...also, do you still need to have work lined up in order to get the visa?? Or is it possible to just get it and then they let you go free and find work on your own? Can it be part-time work? Are we allowed to do some other types of work on the "side" or does it just have to be strict full-time physio?? IF someone can help that would be GREAT since right now I can't find this info anywhere - and the darn visa site gives no email addresses and everytime I call I'm on hold for like 20 minutes and can't wait that long! Ridiculous.

Thanks.