from what i gather on the cic website you have to have a job offer to apply for the skilled workers visa.
is this true??? No. There three routes under skilled worker 1. you have a minimum of one year experience in one of the 38 list as release by the minister, 2. you have arranged employment with a company in Canada, 3. you have one year work experience with a company legally or you are a real international student for one year in Canada.
Read carefully http://www.cic.gc.ca/english/immigrate/skilled/apply-who.asp