Due diligence requires any business to investigate potential partners and vendors from all possible angles. Basic information is readily available if one knows where to look and can include names of business owners, phone numbers, addresses and points of contact. Detailed information about financial statements and legal struggles may be more difficult to dig up -- most businesses are not going to readily reveal this information to the public. However, when information is considered public knowledge, it can be found if a person is willing to do a little research.

Call the business. Depending upon what information is required a simple phone call can return a quick answer. Receptionists and company telephone operators are good resources for basic information such as mailing and email addresses and names and titles for employees in charge of a particular department.

Visit the company's website. Many companies reveal a great deal about their services, products and personnel through their website. Check the "Contact Us" and "About" links online for phone numbers, names and email addresses. Links to investor web pages can provide annual and quarterly financial information.

Contact the state the business is registered in. This is often the state in which the corporate head quarters is located. Business are required to obtain a state business license to conduct business within state boundaries. Each state will have a database filled with registered businesses that may reveal the date the business was started and the person or entity that owns the business. This information is usually public knowledge and available to anyone who looks for it. Some states may provide this information through its official website.

Contact the regulatory agency, if applicable. Businesses that require an industry license such as nightclubs, medical facilities and general contractors will be on file with the appropriate regulatory commission in the state in which they are located. Identify which regulatory board the business might be connected with and inquire about disciplinary action or violations that business might be involved with. The agency may be limited in what they can reveal but many records are public information. Some states may keep records online and are free for anyone to search.

Visit the Better Business Bureau's website. Sometimes the Better Business Bureau may have information on businesses even if they are not members. Complaints and reviews about companies that are members and non-members may reveal information about a business's customer service practices and details about products and service failures.

Consult an online company focused on business information. Online services like Hoovers or Manta contain information about all kinds of businesses both national and international. Search by industry, geography or by business name and discover company revenues, names of personnel, phone numbers and addresses. Detailed reports can be purchased that reveal financial statements, ratios and growth statistics. Experian, Merlin and Lexis Nexis provide access to business information for a fee.

Contact state and local courts to discover liens, lawsuits and judgments. This information is public knowledge and available for those seeking it. However, searching city-by-city or state-by-state can be time consuming. Look for companies that provide business background checks that can reveal this information for a fee.