Marriage Information for US Citizen

I am planning to get married. My sweetheart and I live in Udon Thani. For a number of reasons, I have a timetable for the family/Thai ceremonies that is almost a year away. I would like to get legally married in a way that is recognized by the US government before I do the Thai process.
I have read that it can take a long time to get a visa for your Thai spouse and while we plan on staying in Thailand, I want us to be able to travel to the states together to visit family, so I am anxious to get the process started.
If any of you know the best way to accomplish a civil marriage ceremony I would appreciate your advice.

Thank you,
Casmeri

Have you checked out the US Embassy website.

Marriage in Thailand

A legal marriage in Thailand consists of both parties registering their marriage in person with the local Thai Amphur (Civil Registry Office). The United States does recognize the validity of such a marriage. For American citizens marrying either Thai citizens or another American citizen, the procedure is the same. For Americans marrying a third-country national, their prospective spouse must also follow a similar procedure with their own embassy.

More here:

http://bangkok.usembassy.gov/service/marriage.html