Availability of company financials varies. US based companies which are publicly traded are required to release financials to the Securities Exchange Commission and investors. As a result financials for these types fo companies are publicly available.
Private companies are not required to release their financials publicly. Sometimes limited estimates can be found in Hoovers.
Use Mergent and NetAdvantage to examine publicly traded companies. Mergent contains financial statements which can be easily downloaded as an Excel spreadsheet. NetAdvantage contains current valuation data, financials, stock reports and industry surveys.
US based publicly traded companies will publish and annual report and a 10-K. Check your company's website for these documents.