Marriage means different things to different people, but it usually means lots of different documents. You'll have to fill in a marriage license application for permission to get hitched, then you'll need a marriage license to do the deed. Afterward, you'll receive a marriage certificate. Each document serves a different purpose and some are easier to find for free than others.
Well before you say "I do," you and your fiance need to obtain a marriage license application. You can fill it out, pay a fee and receive your marriage license, which gives official permission for two to become one. If you need to prove that you are or were married in the future, you can obtain a marriage certificate. Some of these documents are public and some are private; some are given different names in different states.
Apply to Get Married
In the United States there is a fee to get married. In most states, the city or county in which you intend to marry requires you to apply for a marriage license before the big day. In the application, you state your names, addresses and other identifying information, and, by signing, swear that you are eligible to marry. This application is generally available free from the city or county administration, and you will find many free on government websites.
Marriage License Application
After your application is accepted and you've paid your fee, you and your fiance are granted a marriage license. This is like a movie ticket; you get to use it once during a specified period of time; in the case of a marriage license, this is usually 90 days, though may vary by state. It costs money to make the application, so obtaining it free is not really an option. But like that movie ticket, once it is used, it doesn't serve much of a purpose and copies generally are neither desirable nor accessible.
Certifying the Matrimonial State
When people talk about getting a copy of a marriage license, they usually mean the marriage certificate or similar document that is issued after vows are exchanged. Generally you can get a copy at the court clerk's office for the cost of a photocopy, but if you want a certified copy, as you likely would for anything official, a higher fee is charged. A certified copy is a copy on which the clerk has fixed a seal, certifying that it is a true and correct copy. If a couple marries in a state that allows confidential marriages for couples already living together, the resulting certificate is also confidential. In California, that means that it is only available to the named parties. Other states distinguish between authorized and informational certificates. They all cost money to obtain.
Order certified copies of marriage certificates from the court clerk's office. Generally you can order them in person or by mail. In some jurisdictions, you also have the option of ordering them on the Internet.