Enter whatever information you have about the Manitoba address you're looking for into an Internet search engine. Most businesses have some sort of online presence, whether it is through a website or listings in online directories. A basic Internet search can often provide you with the street number, street name, city and postal code of a business. Each of these elements is needed in order to send mail in or to Manitoba.
Use the Canadian version of the White Pages, which has been digitized online, to find a personal address. Simply enter the name of the person you are searching for, along with any other information you have, like city or street name. The website will show you a list of matches, along with corresponding addresses. The Canadian White Pages will often allow you to search with only an initial, or a part of a name, though this will usually generate a lot more results.
Visit the Canada Post website, the country's major postal operator. Click the "Find a Postal Code" tab on the company's main page. From there you can find a city mailing address by entering the street number, street name and city. Make sure that the province menu is set to "Manitoba." You can also find rural mailing addresses by using the "PO Box Address" option.
Use the "Reverse Search" or "Find an Address" option on the Canada Post site if you only have the postal code, but not the address of the location you are trying to find. By entering the postal code, the website will tell you the street number, street name, city and even building that the code belongs to, if possible.