This site is a good starting point to find information about a specific
company. It claims to provide among others 15,000 research reports, over
20,000 company profiles and over 1,000 categorised links.
Kompass is a directory of 1.5 million companies in close to 70 countries.
You can use it to find a specific company within a country or to get a
list of companies within a specific industry in a particular country or
region.
This web site lists the 100 largest US companies and the 100 largest non-US
companies available on the web. A very easy way to find the homepage and
additional information for large companies.