That may work for visa applications to other countries, but Canada assesses their visa applicants differently: what scylla said, that you should be able to show that you can support yourself financially even if you have a willing sponsor, applies in a majority of cases.
Also, having family in Canada is seen as a point against you, rather than for you. It makes you more susceptible to overstaying.
To answer the question in your subject: it is not easy to get a Canadian tourist visa. I sometimes think it's even harder than getting a US tourist visa.
If you're still willing to give it a shot, you can start the application process by answering the questionnaire here:
http://www.cic.gc.ca/ctc-vac/getting-started.asp