You apply for entry as the spouse of a UK citizen. You will apply online and pay online. You can make an appointment at some consulates, but you must use the consulate that covers your area of the US. You do not need an appointment, but it's an option. The application is here:

http://www.visa4uk.fco.gov.uk/ApplyNow. ... =Apply+Now

Supporting documents can be sent via FedEx or you can hire a courier. You can also bring them if you have an appointment. You must have the required documents (usually your passport, your spouse's passport or certified copy, birth certificates, bank account statements, pay stubs, proof of accommodation, a letter from the spouse supporting your application, items that prove your relationship, marriage certificate, and anything they ask for or may support your application). If your application is approved, you will receive your FLR and entry clearance visa (stamped in your passport). You will be able to work when you get into the country. You won't have recourse to public funds, but you will have the right to healthcare.

You should apply after you get married. Make sure you enter the UK on or within the 28 days following the valid date of the visa (you will be able to pick the date you plan to travel, but I think it is a 3 month in the future limit). You should make sure you research the financial and accommodation requirements, and to find out suggestions for supporting evidence that your relationship is legit, you've met, and you plan to live together in the UK on a permanent basis.

HTH

 

This will explain how to get working once you're in the country.

http://www.easyexpat.com/forums/forum_47.htm