for job leads:

you can look at the classifieds online, there are often positions posted in schools.

also, many of the international schools here use the usual international education posting sites.

many schools are listed here on QL (see the Guide to Qatar on the bottom right of the webpage), you could check out their web pages.

it should be possible to find good teaching jobs here. you do have to be careful, but many of the international schools are good employers.

good luck!

btw: there are lots of Canadians in Qatar!