There are lots of resources that you can use to find popular information about a country such as their Gross Domestic Product (GDP).
To begin your search, try going to Data subpage of the World Bank website where you can search data sets by country, topic, indicators and more. To find a range of GDP information, go to the 'Indicator' link under the search box.
You'll find GDP information is contained mostly under the 'Economy & Growth' heading.
You may download the information on the indicator web page by clicking the Download Data button beside it.
Seneca Libraries also has a lot of great resources that you can use to find GDP information. Through the library's Country Information guide you can access databases that contain annual country reports.
For example, in the database GlobalData Explorer (formerly Marketline) you can search for country reports that include current, as well as forecast GDP information for a given country. Since many of these reports are long, you may want to use the search function to find the specific information you're looking for. You may also want to browse the other tabs in the International Business guide for additional resources that support your research activities.