Every state may differ in its laws governing people who bartend. Most states do not require a state certified bartending license, but many do require that a bartender take an alcohol awareness/responsible vendor class which is similar to a bartender license. These classes are easily accessible through an online class and may even be administered through a proctor at a local class.
An alcohol awareness or responsible vendor class is issued through vendors such as ServSafe, PSCC, Responsible Vendors, etc. Many times these certificates are paired with a bartender license during the bartending license course you choose to enroll in. Even though many states do not require a bartending license, a bartending certificate deeming you knowledgeable of the effects of alcohol and your local and state laws may be required. No matter what the laws are, it is recommended that you take these classes before you start your bartending career to ensure your safety and to make yourself aware of any and all liabilities that come with this career. It's always better to protect yourself with knowledge.
If you do happen to reside in a state that does require a bartender license or certificate, it is easily and readily obtainable through an online school. These bartending licenses should be a legal alternative to most state sponsored courses. Some states require a bartender license only issued through a state agency, though. Louisiana, for instance, requires you take the certification through a live state sponsored proctor. So, make sure you are aware of your local requirements before signing up for a class to ensure you receive the proper training that your state requires.