Finding information about government and other public sector organizations can be easy or challenging. Most public sector organizations are required to publish their budgets in a publicly-accessible information source--a local newspaper, for example. Meetings are also legally mandated to be open, so minutes may be available. Or, not. Local libraries are often experts in where to find public sector informaiton. Local newspapers sometimes publish databases of salaries. Good goverment organizations sometimes publish information about hearings and meetings. The trick is to find these sources! Google and local newspapers are good starting points.
The U.S. Securities and Exchange Commission (SEC) mandates that companies registered with them (i.e., that are publicly traded companies listed on the stock exchange), disclose specific kinds of information. Much of this information is financial; it also includes names of top executives and members of their board or directors and their compensation, lines of business, subsidiaries, and major actions and changes. This information is issued in documents that are available to the public through EDGAR, the SEC's database, or through third-party organizations that make the reports available and searchable in a variety of formats.
Check these databases for company financials, executives, annual reports, histories, and more.
These website are part of a new trend in which employees write about their jobs and post them to website used by jobseekers. The reviews may give you insight into a company's culture and human resources process, but keep in mind that they are not fact checked and that they represent personal opinion.