When a company decides to pay a dividend, where does that information go first? Lots of site re-publish the dividend but where do they go to find this information quickly?
Go to the stock exchanges where the entity is listed. Under that specific company details, you should be able to find i.e. company filings, details about company reports per quarter, dividends information and much more. Or go to a website like CNN Money or a financial publication like Financial Times. These are reliable sources more so than individual bloggers and the likes of them.
Other way is to go a company's website and to the investor/shareholder's section where they generally post such information. Company website's aren't updated as fast as the stock exchange websites.