i am canadian tourist in milano, need a tourist visa for china, my departure is next week.

According to the rule: An applicant holding a passport other than Italian passport should provide the original and a copy of his or her permanent residence or work permit which should be valid for at least half a year (except for those who enjoy visa or permit exemption for residing or working in Italy), I'm afraid that your application will be denied because you are a tourist in Milan. However, you can still try your luck, please go to China Visa Application Service Center in Milan to submit your application:
Address: Viale Liguria, 40-20143 Milan
Office Hours: 09:00-16:00, Monday - Friday (except public holidays)