Auto insurance is regulated on a state-by-state basis, and your state's insurance department usually has a bunch of relevant information to your search in the consumer information section of its Web site. Search the National Association of Insurance Commissioners State Web Map to find a link to your state insurance department [source: NAIC].
The depth of information varies, but these Web sites often include profiles of the different insurance companies licensed within the state, sample price comparisons charged by competing agencies to cover common vehicles, and consumer guides to auto insurance. Many insurance departments also provide complaint indexes, which tally the number of consumer complaints upheld against a particular company versus the number of policies they have issued. This information can be valuable in determining which company to sign with.
If you're unsure if a prospective insurer is licensed within your state, ask an agent. If the company falsely claims to be licensed in your state, report them.