1. If you want to try to get a temporary work permit as a skilled, you can try looking for jobs at some of these job websites:
http://www.jobbank.gc.ca/http://www.eluta.ca/http://www.monster.ca/http://www.workopolis.com/But you would have to convince them that you are worth the hassle of getting a work permit for you. Bunac would be easier. Spousal should be pretty straight forward but you can't start spousal sponsorship until you are either married or qualify as common law.
2. If your visitor visa was extended to the point that you could live with him for a full year, then you would qualify as common law. If you stay with him while you are applying, you have another 6 months of waiting for a work permit, all in all, 18 months not working if you can afford that.
3. You can be either in or out of Canada. Inside Canada, 6 months to get work permit, 1 to 2 years to get PR, no appeal rights if you are refused, not advised to leave while you are in process. Outside, 7 weeks for sponsorship approval and another 3 to 9 months at London office for PR status and you can travel back and forth while you wait. That is unless you just spent 1 year on a tourist visa and can't get it extended again.
4. Don't know this one.